diff --git a/plugin/turn-manager.ts b/plugin/turn-manager.ts
index 0c4d737..fed88e3 100644
--- a/plugin/turn-manager.ts
+++ b/plugin/turn-manager.ts
@@ -55,8 +55,22 @@ export function getInitializingChannels(): Set<string> {
   return _G._tmInitializingChannels as Set<string>;
 }
 
+/**
+ * Maximum blocked-pending entries tracked per agent per channel.
+ * Caps the drain time: in a busy channel many messages can arrive during a non-speaker
+ * turn, each incrementing the counter. Without a cap the counter grows unboundedly.
+ * Also applied retroactively in markTurnStarted to recover from accumulated debt.
+ */
+const MAX_BLOCKED_PENDING = 3;
+
 export function markTurnStarted(channelId: string, agentId: string): void {
   pendingTurns().add(`${channelId}:${agentId}`);
+  // Cap existing blocked-pending at MAX to recover from accumulated debt
+  // (can occur when many messages arrive during a long non-speaker period).
+  const bpc = blockedPendingCounts();
+  const key = `${channelId}:${agentId}`;
+  const current = bpc.get(key) ?? 0;
+  if (current > MAX_BLOCKED_PENDING) bpc.set(key, MAX_BLOCKED_PENDING);
 }
 
 export function isTurnPending(channelId: string, agentId: string): boolean {
@@ -74,10 +88,12 @@ export function clearTurnPending(channelId: string, agentId: string): void {
  * causing false empty-turn detection. We count them and skip one per agent_end
  * until the count reaches zero, at which point the next agent_end is real.
  */
+
 export function incrementBlockedPending(channelId: string, agentId: string): void {
   const bpc = blockedPendingCounts();
   const key = `${channelId}:${agentId}`;
-  bpc.set(key, (bpc.get(key) ?? 0) + 1);
+  const current = bpc.get(key) ?? 0;
+  if (current < MAX_BLOCKED_PENDING) bpc.set(key, current + 1);
 }
 
 /** Returns true (and decrements) if this agent_end should be treated as a stale blocked completion. */