diff --git a/gateway/platforms/api_server.py b/gateway/platforms/api_server.py
index 027a5a5306a..2e7361c18b4 100644
--- a/gateway/platforms/api_server.py
+++ b/gateway/platforms/api_server.py
@@ -4372,7 +4372,7 @@ class APIServerAdapter(BasePlatformAdapter):
     # BasePlatformAdapter interface
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Start the aiohttp web server."""
         if not AIOHTTP_AVAILABLE:
             logger.warning("[%s] aiohttp not installed", self.name)
diff --git a/gateway/platforms/base.py b/gateway/platforms/base.py
index 9971399c3d9..8dd9fc8fdd4 100644
--- a/gateway/platforms/base.py
+++ b/gateway/platforms/base.py
@@ -2634,10 +2634,21 @@ class BasePlatformAdapter(ABC):
         self._session_store = session_store
     
     @abstractmethod
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """
         Connect to the platform and start receiving messages.
-        
+
+        Args:
+            is_reconnect: False on a cold first boot (the gateway is
+                starting this platform for the first time); True when the
+                reconnect watcher is re-establishing a platform that was
+                previously running and dropped after an outage. Adapters
+                that buffer a server-side update queue (e.g. Telegram's Bot
+                API) should preserve that queue when ``is_reconnect`` is
+                True so messages sent during the outage are delivered rather
+                than silently discarded. Adapters with no such queue may
+                ignore the flag.
+
         Returns True if connection was successful.
         """
         pass
diff --git a/gateway/platforms/bluebubbles.py b/gateway/platforms/bluebubbles.py
index 31595b223b5..d4adbc73153 100644
--- a/gateway/platforms/bluebubbles.py
+++ b/gateway/platforms/bluebubbles.py
@@ -232,7 +232,7 @@ class BlueBubblesAdapter(BasePlatformAdapter):
     # Lifecycle
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         if not self.server_url or not self.password:
             logger.error(
                 "[bluebubbles] BLUEBUBBLES_SERVER_URL and BLUEBUBBLES_PASSWORD are required"
diff --git a/gateway/platforms/msgraph_webhook.py b/gateway/platforms/msgraph_webhook.py
index d1d48996d73..88781d1f547 100644
--- a/gateway/platforms/msgraph_webhook.py
+++ b/gateway/platforms/msgraph_webhook.py
@@ -136,7 +136,7 @@ class MSGraphWebhookAdapter(BasePlatformAdapter):
     def _source_allowlist_required_but_missing(self) -> bool:
         return is_network_accessible(self._host) and not self._allowed_source_networks
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         if self._client_state is None:
             logger.error(
                 "[msgraph_webhook] Refusing to start without extra.client_state configured"
diff --git a/gateway/platforms/signal.py b/gateway/platforms/signal.py
index f91dc96d60f..a3f6916707a 100644
--- a/gateway/platforms/signal.py
+++ b/gateway/platforms/signal.py
@@ -338,7 +338,7 @@ class SignalAdapter(BasePlatformAdapter):
     # Lifecycle
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to signal-cli daemon and start SSE listener."""
         if not self.http_url or not self.account:
             logger.error("Signal: SIGNAL_HTTP_URL and SIGNAL_ACCOUNT are required")
diff --git a/gateway/platforms/webhook.py b/gateway/platforms/webhook.py
index d9f98282a8d..7c77a96b5b8 100644
--- a/gateway/platforms/webhook.py
+++ b/gateway/platforms/webhook.py
@@ -153,7 +153,7 @@ class WebhookAdapter(BasePlatformAdapter):
     # Lifecycle
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         # Load agent-created subscriptions before validating
         self._reload_dynamic_routes()
 
diff --git a/gateway/platforms/weixin.py b/gateway/platforms/weixin.py
index 4ce48719321..4e86dd0bfb9 100644
--- a/gateway/platforms/weixin.py
+++ b/gateway/platforms/weixin.py
@@ -1261,7 +1261,7 @@ class WeixinAdapter(BasePlatformAdapter):
             return [str(item).strip() for item in value if str(item).strip()]
         return [str(value).strip()] if str(value).strip() else []
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         if not check_weixin_requirements():
             message = "Weixin startup failed: aiohttp and cryptography are required"
             self._set_fatal_error("weixin_missing_dependency", message, retryable=False)
diff --git a/gateway/platforms/whatsapp_cloud.py b/gateway/platforms/whatsapp_cloud.py
index 126a79c86b8..c0bf600032c 100644
--- a/gateway/platforms/whatsapp_cloud.py
+++ b/gateway/platforms/whatsapp_cloud.py
@@ -347,7 +347,7 @@ class WhatsAppCloudAdapter(WhatsAppBehaviorMixin, BasePlatformAdapter):
         return super()._is_dm_allowed(sender_id)
 
     # ------------------------------------------------------------------ lifecycle
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         if not check_whatsapp_cloud_requirements():
             self._set_fatal_error(
                 "whatsapp_cloud_deps_missing",
diff --git a/gateway/platforms/yuanbao.py b/gateway/platforms/yuanbao.py
index ade1273c7f2..7f3b1f34e55 100644
--- a/gateway/platforms/yuanbao.py
+++ b/gateway/platforms/yuanbao.py
@@ -5114,7 +5114,7 @@ class YuanbaoAdapter(BasePlatformAdapter):
         """Yuanbao gates DM/group access at intake via dm_policy/group_policy."""
         return True
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to Yuanbao WS gateway and authenticate.
 
         Delegates to ConnectionManager.open().
diff --git a/gateway/run.py b/gateway/run.py
index 9d31cc2a60e..01429983e47 100644
--- a/gateway/run.py
+++ b/gateway/run.py
@@ -3086,13 +3086,24 @@ class GatewayRunner(GatewayAuthorizationMixin, GatewayKanbanWatchersMixin, Gatew
                 return max(0.0, timeout)
         return _PLATFORM_CONNECT_TIMEOUT_SECS_DEFAULT
 
-    async def _connect_adapter_with_timeout(self, adapter, platform) -> bool:
-        """Connect an adapter without allowing one platform to block others."""
+    async def _connect_adapter_with_timeout(
+        self, adapter, platform, *, is_reconnect: bool = False
+    ) -> bool:
+        """Connect an adapter without allowing one platform to block others.
+
+        ``is_reconnect`` is forwarded to ``adapter.connect()`` so platform
+        adapters can distinguish a cold first boot (drop any stale
+        server-side queue) from a watcher reconnect after a prolonged outage
+        (preserve the queue so messages sent during the outage are delivered
+        rather than silently dropped — #46621).
+        """
         timeout = self._platform_connect_timeout_secs()
         if timeout <= 0:
-            return await adapter.connect()
+            return await adapter.connect(is_reconnect=is_reconnect)
         try:
-            return await asyncio.wait_for(adapter.connect(), timeout=timeout)
+            return await asyncio.wait_for(
+                adapter.connect(is_reconnect=is_reconnect), timeout=timeout
+            )
         except asyncio.TimeoutError as exc:
             raise TimeoutError(
                 f"{platform.value} connect timed out after {timeout:g}s"
@@ -6718,7 +6729,12 @@ class GatewayRunner(GatewayAuthorizationMixin, GatewayKanbanWatchersMixin, Gatew
                     adapter.set_topic_recovery_fn(self._recover_telegram_topic_thread_id)
                     adapter._busy_text_mode = self._busy_text_mode
 
-                    success = await self._connect_adapter_with_timeout(adapter, platform)
+                    # Reconnect after an outage: preserve the platform's
+                    # server-side update queue so messages sent while the bot
+                    # was offline are delivered rather than dropped (#46621).
+                    success = await self._connect_adapter_with_timeout(
+                        adapter, platform, is_reconnect=True
+                    )
                     if success:
                         self.adapters[platform] = adapter
                         self._sync_voice_mode_state_to_adapter(adapter)
diff --git a/plugins/platforms/dingtalk/adapter.py b/plugins/platforms/dingtalk/adapter.py
index 29abe98ecdf..8017589e350 100644
--- a/plugins/platforms/dingtalk/adapter.py
+++ b/plugins/platforms/dingtalk/adapter.py
@@ -239,7 +239,7 @@ class DingTalkAdapter(BasePlatformAdapter):
 
     # -- Connection lifecycle -----------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to DingTalk via Stream Mode."""
         if not DINGTALK_STREAM_AVAILABLE:
             logger.warning(
diff --git a/plugins/platforms/discord/adapter.py b/plugins/platforms/discord/adapter.py
index 3c07f513b43..3d5369be522 100644
--- a/plugins/platforms/discord/adapter.py
+++ b/plugins/platforms/discord/adapter.py
@@ -859,7 +859,7 @@ class DiscordAdapter(BasePlatformAdapter):
 
         asyncio.create_task(_notify())
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to Discord and start receiving events."""
         if not DISCORD_AVAILABLE:
             logger.error("[%s] discord.py not installed. Run: pip install discord.py", self.name)
diff --git a/plugins/platforms/email/adapter.py b/plugins/platforms/email/adapter.py
index db97dde9cd6..9521d586c6f 100644
--- a/plugins/platforms/email/adapter.py
+++ b/plugins/platforms/email/adapter.py
@@ -548,7 +548,7 @@ class EmailAdapter(BasePlatformAdapter):
             # Retry with IPv4 only.
             return _connect(ipv4_only=True)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to the IMAP server and start polling for new messages."""
         # Validate up front so a missing host surfaces as an actionable config
         # error instead of IMAP4_SSL("") raising the cryptic
diff --git a/plugins/platforms/feishu/adapter.py b/plugins/platforms/feishu/adapter.py
index bf3c49d3b86..c3ce2c29431 100644
--- a/plugins/platforms/feishu/adapter.py
+++ b/plugins/platforms/feishu/adapter.py
@@ -1641,7 +1641,7 @@ class FeishuAdapter(BasePlatformAdapter):
             .build()
         )
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to Feishu/Lark."""
         if not FEISHU_AVAILABLE:
             logger.error("[Feishu] lark-oapi not installed")
diff --git a/plugins/platforms/google_chat/adapter.py b/plugins/platforms/google_chat/adapter.py
index 6f738488123..5deb0e5af4c 100644
--- a/plugins/platforms/google_chat/adapter.py
+++ b/plugins/platforms/google_chat/adapter.py
@@ -761,7 +761,7 @@ class GoogleChatAdapter(BasePlatformAdapter):
     # ------------------------------------------------------------------
     # Connection lifecycle
     # ------------------------------------------------------------------
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Validate config, authenticate, start Pub/Sub pull, resolve bot id."""
         # First call into the heavy google-cloud stack — trigger the lazy
         # import. ``_load_google_modules()`` is idempotent and rebinds the
diff --git a/plugins/platforms/homeassistant/adapter.py b/plugins/platforms/homeassistant/adapter.py
index 1baa3da75ad..6d59a30c0b4 100644
--- a/plugins/platforms/homeassistant/adapter.py
+++ b/plugins/platforms/homeassistant/adapter.py
@@ -98,7 +98,7 @@ class HomeAssistantAdapter(BasePlatformAdapter):
     # Connection lifecycle
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to HA WebSocket API and subscribe to events."""
         if not AIOHTTP_AVAILABLE:
             logger.warning("[%s] aiohttp not installed. Run: pip install aiohttp", self.name)
diff --git a/plugins/platforms/irc/adapter.py b/plugins/platforms/irc/adapter.py
index 804e1dbc041..e78798adbe6 100644
--- a/plugins/platforms/irc/adapter.py
+++ b/plugins/platforms/irc/adapter.py
@@ -152,7 +152,7 @@ class IRCAdapter(BasePlatformAdapter):
 
     # ── Connection lifecycle ──────────────────────────────────────────────
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to the IRC server, register, and join the channel."""
         if not self.server or not self.channel:
             logger.error("IRC: server and channel must be configured")
diff --git a/plugins/platforms/line/adapter.py b/plugins/platforms/line/adapter.py
index 130bb2e2c38..447cf5fb0c8 100644
--- a/plugins/platforms/line/adapter.py
+++ b/plugins/platforms/line/adapter.py
@@ -740,7 +740,7 @@ class LineAdapter(BasePlatformAdapter):
     # Connection lifecycle
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         if not self.channel_access_token or not self.channel_secret:
             self._set_fatal_error(
                 "config_missing",
diff --git a/plugins/platforms/matrix/adapter.py b/plugins/platforms/matrix/adapter.py
index e8623d90a4a..86dc729bd2a 100644
--- a/plugins/platforms/matrix/adapter.py
+++ b/plugins/platforms/matrix/adapter.py
@@ -1135,7 +1135,7 @@ class MatrixAdapter(BasePlatformAdapter):
     # Required overrides
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to the Matrix homeserver and start syncing."""
         from mautrix.api import HTTPAPI
         from mautrix.client import Client
diff --git a/plugins/platforms/mattermost/adapter.py b/plugins/platforms/mattermost/adapter.py
index d52beeb6f6f..7bdab48bb66 100644
--- a/plugins/platforms/mattermost/adapter.py
+++ b/plugins/platforms/mattermost/adapter.py
@@ -256,7 +256,7 @@ class MattermostAdapter(BasePlatformAdapter):
     # Required overrides
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to Mattermost and start the WebSocket listener."""
         import aiohttp
 
diff --git a/plugins/platforms/ntfy/adapter.py b/plugins/platforms/ntfy/adapter.py
index 4ab46cecfb2..88741aa62f5 100644
--- a/plugins/platforms/ntfy/adapter.py
+++ b/plugins/platforms/ntfy/adapter.py
@@ -183,7 +183,7 @@ class NtfyAdapter(BasePlatformAdapter):
 
     # -- Connection lifecycle -----------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to ntfy by starting the streaming subscription task."""
         if not HTTPX_AVAILABLE:
             logger.warning("[%s] httpx not installed. Run: pip install httpx", self.name)
diff --git a/plugins/platforms/photon/adapter.py b/plugins/platforms/photon/adapter.py
index 5a3a160c0fc..9bec435bfec 100644
--- a/plugins/platforms/photon/adapter.py
+++ b/plugins/platforms/photon/adapter.py
@@ -334,7 +334,7 @@ class PhotonAdapter(BasePlatformAdapter):
 
     # -- Connection lifecycle ---------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         if not HTTPX_AVAILABLE:
             self._set_fatal_error(
                 "MISSING_DEP", "httpx not installed", retryable=False
diff --git a/plugins/platforms/raft/adapter.py b/plugins/platforms/raft/adapter.py
index 7f65fa233c2..0a8b1a359b0 100644
--- a/plugins/platforms/raft/adapter.py
+++ b/plugins/platforms/raft/adapter.py
@@ -468,7 +468,7 @@ class RaftAdapter(BasePlatformAdapter):
     def runtime_session(self) -> str:
         return self._runtime_session
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         if not self._bridge_token:
             self._bridge_token = secrets.token_hex(32)
             logger.info("[raft] Auto-generated bridge token")
diff --git a/plugins/platforms/simplex/adapter.py b/plugins/platforms/simplex/adapter.py
index 0b241d588f3..ae4c6be34b6 100644
--- a/plugins/platforms/simplex/adapter.py
+++ b/plugins/platforms/simplex/adapter.py
@@ -208,7 +208,7 @@ class SimplexAdapter(BasePlatformAdapter):
     # Lifecycle
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to the simplex-chat daemon and start the WebSocket listener."""
         try:
             import websockets  # noqa: F401
diff --git a/plugins/platforms/slack/adapter.py b/plugins/platforms/slack/adapter.py
index 5ef300b086f..60f510d7070 100644
--- a/plugins/platforms/slack/adapter.py
+++ b/plugins/platforms/slack/adapter.py
@@ -829,7 +829,7 @@ class SlackAdapter(BasePlatformAdapter):
         # Non-fatal — the user saw the initial ack already.
         return SendResult(success=True, message_id=None)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to Slack via Socket Mode."""
         if not SLACK_AVAILABLE:
             logger.error(
diff --git a/plugins/platforms/sms/adapter.py b/plugins/platforms/sms/adapter.py
index a1edffb8e16..e40ec0ac39a 100644
--- a/plugins/platforms/sms/adapter.py
+++ b/plugins/platforms/sms/adapter.py
@@ -86,7 +86,7 @@ class SmsAdapter(BasePlatformAdapter):
     # Required abstract methods
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         import aiohttp
         from aiohttp import web
 
diff --git a/plugins/platforms/teams/adapter.py b/plugins/platforms/teams/adapter.py
index fdd0905e7f1..bc204b98b38 100644
--- a/plugins/platforms/teams/adapter.py
+++ b/plugins/platforms/teams/adapter.py
@@ -709,7 +709,7 @@ class TeamsAdapter(BasePlatformAdapter):
         # Used to send cards with the correct conversation type (personal/group/channel).
         self._conv_refs: Dict[str, Any] = {}
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         # Lazy-install the Teams SDK on demand (parity with Slack/Discord/etc.),
         # then re-check the module globals it rebinds.
         check_teams_requirements()
diff --git a/plugins/platforms/telegram/adapter.py b/plugins/platforms/telegram/adapter.py
index 00aff1ed815..8ae46cdd358 100644
--- a/plugins/platforms/telegram/adapter.py
+++ b/plugins/platforms/telegram/adapter.py
@@ -2232,7 +2232,7 @@ class TelegramAdapter(BasePlatformAdapter):
                             self.name, topic_name, seed_err,
                         )
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to Telegram via polling or webhook.
 
         By default, uses long polling (outbound connection to Telegram).
@@ -2240,6 +2240,14 @@ class TelegramAdapter(BasePlatformAdapter):
         instead.  Webhook mode is useful for cloud deployments (Fly.io,
         Railway) where inbound HTTP can wake a suspended machine.
 
+        ``is_reconnect`` distinguishes a cold first boot (False — drop any
+        stale Bot API queue) from a watcher reconnect after a prolonged
+        outage (True — preserve the updates Telegram queued while the bot
+        was offline, otherwise every message sent during the outage is
+        silently lost). The in-process network-error ladder and the
+        409-conflict handler already pass ``drop_pending_updates=False``
+        for the same reason; bootstrap follows suit on the reconnect path.
+
         Env vars for webhook mode::
 
             TELEGRAM_WEBHOOK_URL    Public HTTPS URL (e.g. https://app.fly.dev/telegram)
@@ -2476,7 +2484,11 @@ class TelegramAdapter(BasePlatformAdapter):
                     webhook_url=webhook_url,
                     secret_token=webhook_secret,
                     allowed_updates=Update.ALL_TYPES,
-                    drop_pending_updates=True,
+                    # Webhooks are push-based — Telegram does not hold a
+                    # server-side getUpdates queue, so this flag is a no-op
+                    # in practice. Mirror the polling path's reconnect
+                    # semantics for consistency.
+                    drop_pending_updates=not is_reconnect,
                 )
                 self._webhook_mode = True
                 logger.info(
@@ -2509,7 +2521,10 @@ class TelegramAdapter(BasePlatformAdapter):
 
                 await self._app.updater.start_polling(
                     allowed_updates=Update.ALL_TYPES,
-                    drop_pending_updates=True,
+                    # On a cold first boot drop the stale Bot API queue; on a
+                    # watcher reconnect after an outage preserve it so messages
+                    # sent while the bot was offline are delivered (#46621).
+                    drop_pending_updates=not is_reconnect,
                     error_callback=_polling_error_callback,
                 )
             
diff --git a/plugins/platforms/wecom/adapter.py b/plugins/platforms/wecom/adapter.py
index 0d3fe1da3df..7d809c19a2f 100644
--- a/plugins/platforms/wecom/adapter.py
+++ b/plugins/platforms/wecom/adapter.py
@@ -198,7 +198,7 @@ class WeComAdapter(BasePlatformAdapter):
     # Connection lifecycle
     # ------------------------------------------------------------------
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """Connect to the WeCom AI Bot gateway."""
         if not AIOHTTP_AVAILABLE:
             message = "WeCom startup failed: aiohttp not installed"
diff --git a/plugins/platforms/whatsapp/adapter.py b/plugins/platforms/whatsapp/adapter.py
index 5c3d6bbb823..05daeabeed8 100644
--- a/plugins/platforms/whatsapp/adapter.py
+++ b/plugins/platforms/whatsapp/adapter.py
@@ -411,7 +411,7 @@ class WhatsAppAdapter(WhatsAppBehaviorMixin, BasePlatformAdapter):
             return float(default)
         return parsed
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         """
         Start the WhatsApp bridge.
         
diff --git a/tests/gateway/relay/stub_connector.py b/tests/gateway/relay/stub_connector.py
index e309750d5e8..2d9baab3e41 100644
--- a/tests/gateway/relay/stub_connector.py
+++ b/tests/gateway/relay/stub_connector.py
@@ -40,7 +40,7 @@ class StubConnector:
         # absent/expired capability or a tenant mismatch on the connector side.
         self.next_follow_up_result: Dict[str, Any] = {"success": True, "message_id": "f1"}
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         self.connected = True
         return True
 
diff --git a/tests/gateway/relay/test_relay_going_idle.py b/tests/gateway/relay/test_relay_going_idle.py
index 05ed8190734..d2895a87b6b 100644
--- a/tests/gateway/relay/test_relay_going_idle.py
+++ b/tests/gateway/relay/test_relay_going_idle.py
@@ -422,7 +422,7 @@ async def test_adapter_go_dormant_noop_on_stub_transport():
     )
 
     class _StubTransport:
-        async def connect(self):
+        async def connect(self, *, is_reconnect: bool = False):
             return True
 
         def set_inbound_handler(self, h):
diff --git a/tests/gateway/restart_test_helpers.py b/tests/gateway/restart_test_helpers.py
index 77c56ec40eb..eac9c44c651 100644
--- a/tests/gateway/restart_test_helpers.py
+++ b/tests/gateway/restart_test_helpers.py
@@ -15,7 +15,7 @@ class RestartTestAdapter(BasePlatformAdapter):
         self.sent: list[str] = []
         self.sent_calls: list[tuple[str, str, object]] = []
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         return True
 
     async def disconnect(self):
diff --git a/tests/gateway/test_active_session_text_merge.py b/tests/gateway/test_active_session_text_merge.py
index 16d40815ba2..88f1b6cfeb8 100644
--- a/tests/gateway/test_active_session_text_merge.py
+++ b/tests/gateway/test_active_session_text_merge.py
@@ -65,7 +65,7 @@ def _make_event(
 
 
 class _DummyAdapter(BasePlatformAdapter):  # type: ignore[misc]
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         pass
 
     async def disconnect(self):
diff --git a/tests/gateway/test_base_topic_sessions.py b/tests/gateway/test_base_topic_sessions.py
index dd2ef3a1262..4de540b49d1 100644
--- a/tests/gateway/test_base_topic_sessions.py
+++ b/tests/gateway/test_base_topic_sessions.py
@@ -20,7 +20,7 @@ class DummyTelegramAdapter(BasePlatformAdapter):
         self.typing = []
         self.processing_hooks = []
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_cancel_background_drain.py b/tests/gateway/test_cancel_background_drain.py
index c95fdc062eb..8f8c7694cde 100644
--- a/tests/gateway/test_cancel_background_drain.py
+++ b/tests/gateway/test_cancel_background_drain.py
@@ -19,7 +19,7 @@ from gateway.session import SessionSource, build_session_key
 
 
 class _StubAdapter(BasePlatformAdapter):
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         pass
 
     async def disconnect(self):
diff --git a/tests/gateway/test_command_bypass_active_session.py b/tests/gateway/test_command_bypass_active_session.py
index e5e8a4fa469..b741f667edd 100644
--- a/tests/gateway/test_command_bypass_active_session.py
+++ b/tests/gateway/test_command_bypass_active_session.py
@@ -29,7 +29,7 @@ from gateway.session import SessionSource, build_session_key
 class _StubAdapter(BasePlatformAdapter):
     """Concrete adapter with abstract methods stubbed out."""
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         pass
 
     async def disconnect(self):
diff --git a/tests/gateway/test_duplicate_reply_suppression.py b/tests/gateway/test_duplicate_reply_suppression.py
index c7c047fdb65..8d1a36e978e 100644
--- a/tests/gateway/test_duplicate_reply_suppression.py
+++ b/tests/gateway/test_duplicate_reply_suppression.py
@@ -37,7 +37,7 @@ class StubAdapter(BasePlatformAdapter):
         super().__init__(PlatformConfig(enabled=True, token="fake"), Platform.DISCORD)
         self.sent = []
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         return True
 
     async def disconnect(self):
diff --git a/tests/gateway/test_ephemeral_reply.py b/tests/gateway/test_ephemeral_reply.py
index 61b70748e16..1ed1237f2cc 100644
--- a/tests/gateway/test_ephemeral_reply.py
+++ b/tests/gateway/test_ephemeral_reply.py
@@ -39,7 +39,7 @@ from gateway.session import SessionSource
 class _NoDeleteAdapter(BasePlatformAdapter):
     """Adapter that does NOT override delete_message (silent degrade)."""
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         pass
 
     async def disconnect(self):
@@ -59,7 +59,7 @@ class _DeleteCapableAdapter(BasePlatformAdapter):
         super().__init__(*a, **kw)
         self.deleted: list[tuple[str, str]] = []
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         pass
 
     async def disconnect(self):
diff --git a/tests/gateway/test_interrupt_key_match.py b/tests/gateway/test_interrupt_key_match.py
index 3a703c0261d..5e206e6cf43 100644
--- a/tests/gateway/test_interrupt_key_match.py
+++ b/tests/gateway/test_interrupt_key_match.py
@@ -21,7 +21,7 @@ class StubAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="test"), Platform.TELEGRAM)
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         return True
 
     async def disconnect(self):
diff --git a/tests/gateway/test_keep_typing_timeout.py b/tests/gateway/test_keep_typing_timeout.py
index 6d6a1624ca5..e303f103495 100644
--- a/tests/gateway/test_keep_typing_timeout.py
+++ b/tests/gateway/test_keep_typing_timeout.py
@@ -38,7 +38,7 @@ class _StubAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="test"), Platform.TELEGRAM)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_pending_drain_no_recursion.py b/tests/gateway/test_pending_drain_no_recursion.py
index b7569b8d02b..35a1348e50f 100644
--- a/tests/gateway/test_pending_drain_no_recursion.py
+++ b/tests/gateway/test_pending_drain_no_recursion.py
@@ -35,7 +35,7 @@ from gateway.session import SessionSource, build_session_key
 
 
 class _StubAdapter(BasePlatformAdapter):
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         pass
 
     async def disconnect(self):
diff --git a/tests/gateway/test_pending_drain_race.py b/tests/gateway/test_pending_drain_race.py
index 810d52e9e2a..0d46fb6bd6d 100644
--- a/tests/gateway/test_pending_drain_race.py
+++ b/tests/gateway/test_pending_drain_race.py
@@ -36,7 +36,7 @@ from gateway.session import SessionSource, build_session_key
 
 
 class _StubAdapter(BasePlatformAdapter):
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         pass
 
     async def disconnect(self):
diff --git a/tests/gateway/test_platform_base.py b/tests/gateway/test_platform_base.py
index 60b69e000be..c2b7a2c8749 100644
--- a/tests/gateway/test_platform_base.py
+++ b/tests/gateway/test_platform_base.py
@@ -1276,7 +1276,7 @@ class TestTruncateMessage:
         """Create a minimal adapter instance for testing static/instance methods."""
 
         class StubAdapter(BasePlatformAdapter):
-            async def connect(self):
+            async def connect(self, *, is_reconnect: bool = False):
                 return True
 
             async def disconnect(self):
diff --git a/tests/gateway/test_platform_reconnect.py b/tests/gateway/test_platform_reconnect.py
index 80835f2146b..2f8a0c98943 100644
--- a/tests/gateway/test_platform_reconnect.py
+++ b/tests/gateway/test_platform_reconnect.py
@@ -26,8 +26,12 @@ class StubAdapter(BasePlatformAdapter):
         self._succeed = succeed
         self._fatal_error = fatal_error
         self._fatal_retryable = fatal_retryable
+        # Records the is_reconnect value of every connect() call so tests can
+        # assert that the watcher distinguishes reconnect from cold boot (#46621).
+        self.connect_calls: list[bool] = []
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
+        self.connect_calls.append(is_reconnect)
         if self._fatal_error:
             self._set_fatal_error("test_error", self._fatal_error, retryable=self._fatal_retryable)
             return False
@@ -140,7 +144,7 @@ class TestStartupPlatformIsolation:
         runner = _make_runner()
         adapter = StubAdapter()
 
-        async def hang():
+        async def hang(*, is_reconnect: bool = False):
             await asyncio.sleep(60)
             return True
 
@@ -217,6 +221,59 @@ class TestPlatformReconnectWatcher:
         assert Platform.TELEGRAM not in runner._failed_platforms
         assert Platform.TELEGRAM in runner.adapters
 
+    @pytest.mark.asyncio
+    async def test_reconnect_passes_is_reconnect_true(self):
+        """The watcher must connect with is_reconnect=True so adapters preserve
+        their server-side update queue across an outage (#46621). Without this,
+        bootstrap start_polling(drop_pending_updates=True) silently dropped every
+        message queued while the bot was offline."""
+        runner = _make_runner()
+        runner._sync_voice_mode_state_to_adapter = MagicMock()
+
+        runner._failed_platforms[Platform.TELEGRAM] = {
+            "config": PlatformConfig(enabled=True, token="test"),
+            "attempts": 1,
+            "next_retry": time.monotonic() - 1,
+        }
+
+        succeed_adapter = StubAdapter(succeed=True)
+        real_sleep = asyncio.sleep
+
+        with patch.object(runner, "_create_adapter", return_value=succeed_adapter):
+            with patch("gateway.run.build_channel_directory", create=True):
+                runner._running = True
+                call_count = 0
+
+                async def fake_sleep(n):
+                    nonlocal call_count
+                    call_count += 1
+                    if call_count > 1:
+                        runner._running = False
+                    await real_sleep(0)
+
+                with patch("asyncio.sleep", side_effect=fake_sleep):
+                    await runner._platform_reconnect_watcher()
+
+        assert succeed_adapter.connect_calls == [True], (
+            f"watcher must pass is_reconnect=True; got {succeed_adapter.connect_calls!r}"
+        )
+        assert Platform.TELEGRAM in runner.adapters
+
+    @pytest.mark.asyncio
+    async def test_cold_connect_defaults_to_is_reconnect_false(self):
+        """The cold-start connect path (_connect_adapter_with_timeout with no
+        is_reconnect arg) must default to False so a first boot still drops any
+        stale queue (#46621)."""
+        runner = _make_runner()
+        adapter = StubAdapter(succeed=True)
+
+        success = await runner._connect_adapter_with_timeout(adapter, Platform.TELEGRAM)
+
+        assert success is True
+        assert adapter.connect_calls == [False], (
+            f"cold-start must default to is_reconnect=False; got {adapter.connect_calls!r}"
+        )
+
     @pytest.mark.asyncio
     async def test_reconnect_retries_resume_pending_for_platform(self):
         """A successful reconnect retries the startup auto-resume scoped to
diff --git a/tests/gateway/test_platform_reconnect_fd_leak.py b/tests/gateway/test_platform_reconnect_fd_leak.py
index 221cf55ee27..bc31a9fc010 100644
--- a/tests/gateway/test_platform_reconnect_fd_leak.py
+++ b/tests/gateway/test_platform_reconnect_fd_leak.py
@@ -103,7 +103,7 @@ class _CountingAdapter(BasePlatformAdapter):
         self._fatal_retryable = fatal_retryable
         self._raise_during_connect = raise_during_connect
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         if self._raise_during_connect:
             raise RuntimeError("simulated connect exception")
         if self._fatal_error:
@@ -254,7 +254,7 @@ class TestReconnectFDLeakRegression:
                     Platform.TELEGRAM,
                 )
 
-            async def connect(self) -> bool:
+            async def connect(self, *, is_reconnect: bool = False) -> bool:
                 return True
 
             async def disconnect(self) -> None:
diff --git a/tests/gateway/test_post_delivery_callback_chaining.py b/tests/gateway/test_post_delivery_callback_chaining.py
index 38c1978f0fc..db0ddb3577f 100644
--- a/tests/gateway/test_post_delivery_callback_chaining.py
+++ b/tests/gateway/test_post_delivery_callback_chaining.py
@@ -13,7 +13,7 @@ from gateway.platforms.base import BasePlatformAdapter, SendResult
 
 
 class _MinAdapter(BasePlatformAdapter):
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_queue_consumption.py b/tests/gateway/test_queue_consumption.py
index 792d7b7ea52..ec1b0dedc83 100644
--- a/tests/gateway/test_queue_consumption.py
+++ b/tests/gateway/test_queue_consumption.py
@@ -27,7 +27,7 @@ class _StubAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="test"), Platform.TELEGRAM)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_relay_capability_surface.py b/tests/gateway/test_relay_capability_surface.py
index da36f0ac4f8..ad1e7b45da0 100644
--- a/tests/gateway/test_relay_capability_surface.py
+++ b/tests/gateway/test_relay_capability_surface.py
@@ -22,7 +22,7 @@ from gateway.platforms.base import BasePlatformAdapter
 class _MinAdapter(BasePlatformAdapter):
     """Smallest concrete adapter: implements exactly the abstract methods."""
 
-    async def connect(self):  # pragma: no cover - not called
+    async def connect(self, *, is_reconnect: bool = False):  # pragma: no cover - not called
         return True
 
     async def disconnect(self):  # pragma: no cover - not called
diff --git a/tests/gateway/test_run_cleanup_progress.py b/tests/gateway/test_run_cleanup_progress.py
index dfb5ef03342..466f83f5dc1 100644
--- a/tests/gateway/test_run_cleanup_progress.py
+++ b/tests/gateway/test_run_cleanup_progress.py
@@ -41,7 +41,7 @@ class CleanupCaptureAdapter(BasePlatformAdapter):
         self.edits = []
         self.deleted = []
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_run_progress_interrupt.py b/tests/gateway/test_run_progress_interrupt.py
index cc25b8db868..de047e0fe29 100644
--- a/tests/gateway/test_run_progress_interrupt.py
+++ b/tests/gateway/test_run_progress_interrupt.py
@@ -28,7 +28,7 @@ class ProgressCaptureAdapter(BasePlatformAdapter):
         self.edits = []
         self.typing = []
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_run_progress_topics.py b/tests/gateway/test_run_progress_topics.py
index c91b5a0a4c9..fed22fa7782 100644
--- a/tests/gateway/test_run_progress_topics.py
+++ b/tests/gateway/test_run_progress_topics.py
@@ -22,7 +22,7 @@ class ProgressCaptureAdapter(BasePlatformAdapter):
         self.edits = []
         self.typing = []
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_runner_fatal_adapter.py b/tests/gateway/test_runner_fatal_adapter.py
index 706514f1ae6..7e7739582d1 100644
--- a/tests/gateway/test_runner_fatal_adapter.py
+++ b/tests/gateway/test_runner_fatal_adapter.py
@@ -11,7 +11,7 @@ class _FatalAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="token"), Platform.TELEGRAM)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         self._set_fatal_error(
             "telegram_token_lock",
             "Another local Hermes gateway is already using this Telegram bot token.",
@@ -33,7 +33,7 @@ class _RuntimeRetryableAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="token"), Platform.WHATSAPP)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_runner_startup_failures.py b/tests/gateway/test_runner_startup_failures.py
index 12aa5c4a3d8..4a1343ae768 100644
--- a/tests/gateway/test_runner_startup_failures.py
+++ b/tests/gateway/test_runner_startup_failures.py
@@ -12,7 +12,7 @@ class _RetryableFailureAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="***"), Platform.TELEGRAM)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         self._set_fatal_error(
             "telegram_connect_error",
             "Telegram startup failed: temporary DNS resolution failure.",
@@ -34,7 +34,7 @@ class _DisabledAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=False, token="***"), Platform.TELEGRAM)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         raise AssertionError("connect should not be called for disabled platforms")
 
     async def disconnect(self) -> None:
@@ -51,7 +51,7 @@ class _SuccessfulAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="***"), Platform.DISCORD)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
@@ -467,7 +467,7 @@ class _NonRetryableFailureAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="***"), Platform.DISCORD)
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         self._set_fatal_error(
             "discord-bot-token_lock",
             "Discord bot token already in use (PID 999). Stop the other gateway first.",
diff --git a/tests/gateway/test_send_multiple_images.py b/tests/gateway/test_send_multiple_images.py
index 590a763acc3..77acf205296 100644
--- a/tests/gateway/test_send_multiple_images.py
+++ b/tests/gateway/test_send_multiple_images.py
@@ -41,7 +41,7 @@ class _StubAdapter(BasePlatformAdapter):
         self.sent_animations = []
         self.sent_files = []
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         return True
 
     async def disconnect(self):
diff --git a/tests/gateway/test_send_retry.py b/tests/gateway/test_send_retry.py
index c57a7712e3d..75de6cd88eb 100644
--- a/tests/gateway/test_send_retry.py
+++ b/tests/gateway/test_send_retry.py
@@ -35,7 +35,7 @@ class _StubAdapter(BasePlatformAdapter):
         self._send_calls.append((chat_id, content))
         return self._next_result()
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_session_hygiene.py b/tests/gateway/test_session_hygiene.py
index ccec24db53c..10bcf00cede 100644
--- a/tests/gateway/test_session_hygiene.py
+++ b/tests/gateway/test_session_hygiene.py
@@ -56,7 +56,7 @@ class HygieneCaptureAdapter(BasePlatformAdapter):
         super().__init__(PlatformConfig(enabled=True, token="fake-token"), Platform.TELEGRAM)
         self.sent = []
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_session_split_brain_11016.py b/tests/gateway/test_session_split_brain_11016.py
index 4a00f31b138..b402f2aa529 100644
--- a/tests/gateway/test_session_split_brain_11016.py
+++ b/tests/gateway/test_session_split_brain_11016.py
@@ -37,7 +37,7 @@ from gateway.session import SessionSource, build_session_key
 
 
 class _StubAdapter(BasePlatformAdapter):
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         pass
 
     async def disconnect(self):
diff --git a/tests/gateway/test_status_command.py b/tests/gateway/test_status_command.py
index f02738b51f2..39ea4e3ff13 100644
--- a/tests/gateway/test_status_command.py
+++ b/tests/gateway/test_status_command.py
@@ -611,7 +611,7 @@ async def test_status_command_bypasses_active_session_guard():
     class _ConcreteAdapter(BasePlatformAdapter):
         platform = Platform.TELEGRAM
 
-        async def connect(self): pass
+        async def connect(self, *, is_reconnect: bool = False): pass
         async def disconnect(self): pass
         async def send(self, chat_id, content, **kwargs): pass
         async def get_chat_info(self, chat_id): return {}
@@ -692,7 +692,7 @@ async def test_post_delivery_callback_generation_snapshot_happens_after_bind():
     class _ConcreteAdapter(BasePlatformAdapter):
         platform = Platform.TELEGRAM
 
-        async def connect(self): pass
+        async def connect(self, *, is_reconnect: bool = False): pass
         async def disconnect(self): pass
         async def send(self, chat_id, content, **kwargs): pass
         async def get_chat_info(self, chat_id): return {}
diff --git a/tests/gateway/test_telegram_clarify_buttons.py b/tests/gateway/test_telegram_clarify_buttons.py
index 81cb5c97ac5..70a06087a44 100644
--- a/tests/gateway/test_telegram_clarify_buttons.py
+++ b/tests/gateway/test_telegram_clarify_buttons.py
@@ -403,7 +403,7 @@ class TestBaseAdapterClarifyFallback:
                 # Skip base __init__ — we're not exercising it
                 self.sent: list = []
 
-            async def connect(self): pass
+            async def connect(self, *, is_reconnect: bool = False): pass
             async def disconnect(self): pass
             async def send(self, chat_id, content, **kw):
                 self.sent.append({"chat_id": chat_id, "content": content})
@@ -436,7 +436,7 @@ class TestBaseAdapterClarifyFallback:
             name = "stub"
             def __init__(self):
                 self.sent: list = []
-            async def connect(self): pass
+            async def connect(self, *, is_reconnect: bool = False): pass
             async def disconnect(self): pass
             async def send(self, chat_id, content, **kw):
                 self.sent.append(content)
diff --git a/tests/gateway/test_telegram_conflict.py b/tests/gateway/test_telegram_conflict.py
index 31137212d74..def45a822d7 100644
--- a/tests/gateway/test_telegram_conflict.py
+++ b/tests/gateway/test_telegram_conflict.py
@@ -425,3 +425,67 @@ async def test_polling_conflict_reschedule_uses_running_loop(monkeypatch):
     except (asyncio.CancelledError, Exception):
         pass
     await _cancel_heartbeat(adapter)
+
+
+def _build_polling_app(monkeypatch):
+    """Wire a mock PTB Application whose start_polling captures kwargs."""
+    captured = {}
+
+    async def fake_start_polling(**kwargs):
+        captured.update(kwargs)
+
+    updater = SimpleNamespace(
+        start_polling=AsyncMock(side_effect=fake_start_polling),
+        stop=AsyncMock(),
+        running=True,
+    )
+    bot = SimpleNamespace(set_my_commands=AsyncMock(), delete_webhook=AsyncMock())
+    app = SimpleNamespace(
+        bot=bot,
+        updater=updater,
+        add_handler=MagicMock(),
+        initialize=AsyncMock(),
+        start=AsyncMock(),
+    )
+    builder = MagicMock()
+    builder.token.return_value = builder
+    builder.request.return_value = builder
+    builder.get_updates_request.return_value = builder
+    builder.build.return_value = app
+    monkeypatch.setattr(
+        "plugins.platforms.telegram.adapter.Application",
+        SimpleNamespace(builder=MagicMock(return_value=builder)),
+    )
+    monkeypatch.setattr(
+        "gateway.status.acquire_scoped_lock",
+        lambda scope, identity, metadata=None: (True, None),
+    )
+    monkeypatch.setattr("asyncio.sleep", AsyncMock())
+    return captured
+
+
+@pytest.mark.asyncio
+async def test_cold_connect_drops_pending_updates(monkeypatch):
+    """A cold first boot (is_reconnect=False) drops the stale Bot API queue."""
+    adapter = TelegramAdapter(PlatformConfig(enabled=True, token="***"))
+    captured = _build_polling_app(monkeypatch)
+
+    ok = await adapter.connect()  # default is_reconnect=False
+
+    assert ok is True
+    assert captured["drop_pending_updates"] is True
+    await _cancel_heartbeat(adapter)
+
+
+@pytest.mark.asyncio
+async def test_reconnect_preserves_pending_updates(monkeypatch):
+    """A watcher reconnect (is_reconnect=True) preserves the queue Telegram
+    accumulated during the outage — the core of #46621."""
+    adapter = TelegramAdapter(PlatformConfig(enabled=True, token="***"))
+    captured = _build_polling_app(monkeypatch)
+
+    ok = await adapter.connect(is_reconnect=True)
+
+    assert ok is True
+    assert captured["drop_pending_updates"] is False
+    await _cancel_heartbeat(adapter)
diff --git a/tests/gateway/test_telegram_thread_fallback.py b/tests/gateway/test_telegram_thread_fallback.py
index 20b38a7cbe4..719b1367846 100644
--- a/tests/gateway/test_telegram_thread_fallback.py
+++ b/tests/gateway/test_telegram_thread_fallback.py
@@ -1127,7 +1127,7 @@ async def test_base_send_image_fallback_preserves_metadata():
     from gateway.platforms.base import BasePlatformAdapter
 
     class _ConcreteBaseAdapter(BasePlatformAdapter):
-        async def connect(self):
+        async def connect(self, *, is_reconnect: bool = False):
             return True
 
         async def disconnect(self):
diff --git a/tests/gateway/test_tool_response_drop_recovery.py b/tests/gateway/test_tool_response_drop_recovery.py
index b4a5a1063ab..f39362b30c8 100644
--- a/tests/gateway/test_tool_response_drop_recovery.py
+++ b/tests/gateway/test_tool_response_drop_recovery.py
@@ -40,7 +40,7 @@ class _DummyAdapter(BasePlatformAdapter):
         super().__init__(PlatformConfig(enabled=True, token="fake-token"), platform)
         self.sent: list[dict] = []
 
-    async def connect(self) -> bool:
+    async def connect(self, *, is_reconnect: bool = False) -> bool:
         return True
 
     async def disconnect(self) -> None:
diff --git a/tests/gateway/test_tts_media_routing.py b/tests/gateway/test_tts_media_routing.py
index 016be97ea27..e152b99c274 100644
--- a/tests/gateway/test_tts_media_routing.py
+++ b/tests/gateway/test_tts_media_routing.py
@@ -22,7 +22,7 @@ class _MediaRoutingAdapter(BasePlatformAdapter):
     def __init__(self):
         super().__init__(PlatformConfig(enabled=True, token="test"), Platform.TELEGRAM)
 
-    async def connect(self):
+    async def connect(self, *, is_reconnect: bool = False):
         return True
 
     async def disconnect(self):
diff --git a/tests/tools/test_send_message_tool.py b/tests/tools/test_send_message_tool.py
index dcdb8f83266..d9c0b64b7ab 100644
--- a/tests/tools/test_send_message_tool.py
+++ b/tests/tools/test_send_message_tool.py
@@ -871,7 +871,7 @@ class TestSendToPlatformChunking:
             def __init__(self, _config):
                 self.connected = False
 
-            async def connect(self):
+            async def connect(self, *, is_reconnect: bool = False):
                 self.connected = True
                 calls.append(("connect",))
                 return True