diff --git a/src/auto-reply/reply/queue/drain.ts b/src/auto-reply/reply/queue/drain.ts
index cabba31273b..e6cfeee2de7 100644
--- a/src/auto-reply/reply/queue/drain.ts
+++ b/src/auto-reply/reply/queue/drain.ts
@@ -9,6 +9,7 @@ import {
   drainCollectQueueStep,
   drainNextQueueItem,
   hasCrossChannelItems,
+  removeQueuedItemsByRef,
   previewQueueSummaryPrompt,
   waitForQueueDebounce,
 } from "../../../utils/queue-helpers.js";
@@ -497,7 +498,7 @@ export function scheduleFollowupDrain(
             } else {
               await drainGroup();
             }
-            queue.items.splice(0, groupItems.length);
+            removeQueuedItemsByRef(queue.items, groupItems);
             if (pendingSummary) {
               clearFollowupQueueSummaryState(queue);
               pendingSummary = undefined;
diff --git a/src/utils/queue-helpers.ts b/src/utils/queue-helpers.ts
index 89b9f2c7c7a..b1933d8b927 100644
--- a/src/utils/queue-helpers.ts
+++ b/src/utils/queue-helpers.ts
@@ -166,6 +166,15 @@ export function beginQueueDrain<T extends { draining: boolean }>(
   return queue;
 }
 
+export function removeQueuedItemsByRef<T>(items: T[], processed: readonly T[]): void {
+  for (const item of processed) {
+    const idx = items.indexOf(item);
+    if (idx !== -1) {
+      items.splice(idx, 1);
+    }
+  }
+}
+
 /** Run and remove the next queued item, returning false when empty. */
 export async function drainNextQueueItem<T>(
   items: T[],
@@ -176,7 +185,7 @@ export async function drainNextQueueItem<T>(
     return false;
   }
   await run(next);
-  items.shift();
+  removeQueuedItemsByRef(items, [next]);
   return true;
 }