diff --git a/app/shared/src/commonMain/kotlin/iris/state/IrisController.kt b/app/shared/src/commonMain/kotlin/iris/state/IrisController.kt
index 77034c0..000719b 100644
--- a/app/shared/src/commonMain/kotlin/iris/state/IrisController.kt
+++ b/app/shared/src/commonMain/kotlin/iris/state/IrisController.kt
@@ -95,6 +95,8 @@ import kotlinx.coroutines.launch
 import java.util.Collections
 import java.util.concurrent.atomic.AtomicLong
 import kotlin.random.Random
+import kotlin.time.TimeMark
+import kotlin.time.TimeSource
 
 /**
  * App-level controller (M3): owns the GatewayClient + ChatStore + ChannelStore,
@@ -188,13 +190,34 @@ class IrisController(
         _foreground.value = fg
     }
 
+    /** M8: the last message id whose arrival incremented [lane]'s unread
+     *  badge. The same finalized message can be delivered twice (live SSE
+     *  plus the sync replay after a push-triggered reconnect) — only the
+     *  first delivery may count. Frame-handler coroutine only. */
+    private val countedMessageIds = HashMap<String, String>()
+
+    /** M5/M8: when a high-priority notification banner (cron/approval/clarify)
+     *  was last posted per lane. Cron delivery = notification frame + message
+     *  frame; the banner already announced the delivery, so the accompanying
+     *  message frame must not post a second system notification. Frame-handler
+     *  coroutine only. */
+    private val lastHighPriorityBannerAt = HashMap<String, TimeMark>()
+
     /** M8: a finalized assistant message arrived in [lane]. Count it as unread
      *  unless the user is actively reading that lane right now (it is the
      *  current lane, the app is focused, and the newest content is at the
-     *  bottom of the viewport). */
-    private fun noteIncomingAssistantMessage(lane: String) {
+     *  bottom of the viewport). [messageId] dedupes redeliveries of the same
+     *  frame (see [countedMessageIds]). */
+    private fun noteIncomingAssistantMessage(
+        lane: String,
+        messageId: String?,
+    ) {
+        if (messageId != null && countedMessageIds[lane] == messageId) return
         val beingRead = lane == chat.currentLane.value && isAppForeground() && currentLaneAtBottom
-        if (!beingRead) chat.markUnread(lane)
+        if (!beingRead) {
+            if (messageId != null) countedMessageIds[lane] = messageId
+            chat.markUnread(lane)
+        }
     }
 
     /** M8: the user is now viewing the current lane's newest content — clear
@@ -332,6 +355,11 @@ class IrisController(
         /** Max simultaneous banners; persistent ones are exempt from the cap. */
         private const val MAX_BANNERS = 5
 
+        /** Window in which a high-priority banner suppresses the system
+         *  notification for its accompanying message frame (mirrors the
+         *  gateway's push-coalesce window, classify._PUSH_COALESCE_S). */
+        private const val BANNER_NOTIFY_SUPPRESS_MS = 5_000L
+
         const val FONT_SCALE_MIN = 0.8f
         const val FONT_SCALE_MAX = 1.5f
 
@@ -523,6 +551,13 @@ class IrisController(
     ) {
         if (isAppForeground()) return
         if (text.isBlank()) return
+        // A high-priority banner (cron/approval/clarify) for this lane just
+        // announced this delivery — don't stack a second notification for the
+        // accompanying message frame.
+        chatId?.let { cid ->
+            val mark = lastHighPriorityBannerAt[chat.laneKey(cid, threadId)]
+            if (mark != null && mark.elapsedNow().inWholeMilliseconds < BANNER_NOTIFY_SUPPRESS_MS) return
+        }
         val id = chatId ?: "default"
         val chatName = channels.byId(id)?.name
         postSystemNotification(id, chatName, chatName ?: "Iris", preview(text), threadId)
@@ -647,7 +682,7 @@ class IrisController(
                                         // content — count it as unread unless the
                                         // user is reading this lane right now.
                                         frame.chatId?.let { cid ->
-                                            noteIncomingAssistantMessage(chat.laneKey(cid, frame.threadId))
+                                            noteIncomingAssistantMessage(chat.laneKey(cid, frame.threadId), it.messageId)
                                         }
                                         if (!alreadyConsumed && !isPushedReplay(frame)) {
                                             notifyMessageIfBackgrounded(frame.chatId, frame.threadId, it.finalText)
@@ -660,7 +695,7 @@ class IrisController(
                                         if (it.role == ROLE_ASSISTANT) {
                                             // M8: a finalized (non-streaming) reply.
                                             frame.chatId?.let { cid ->
-                                                noteIncomingAssistantMessage(chat.laneKey(cid, frame.threadId))
+                                                noteIncomingAssistantMessage(chat.laneKey(cid, frame.threadId), it.messageId)
                                             }
                                             if (!alreadyConsumed && !isPushedReplay(frame)) {
                                                 notifyMessageIfBackgrounded(frame.chatId, frame.threadId, it.text)
@@ -787,6 +822,15 @@ class IrisController(
                                 // sync replay) must not re-show the banner.
                                 if (!alreadyConsumed) {
                                     pushBanner(p.kind, p.title, p.body, p.chatId, p.threadId)
+                                    // Cron delivery = notification frame + message frame: remember
+                                    // that the banner announced this lane so the message frame
+                                    // doesn't post a second system notification.
+                                    if (p.kind in HIGH_PRIORITY_NOTIF_KINDS) {
+                                        p.chatId?.let { cid ->
+                                            lastHighPriorityBannerAt[chat.laneKey(cid, p.threadId)] =
+                                                TimeSource.Monotonic.markNow()
+                                        }
+                                    }
                                     // M5: the connection is live but the app is backgrounded — the
                                     // in-app banner is invisible, so mirror to a system
                                     // notification (the push backend only fires when