diff --git a/src/cron/service.runs-one-shot-main-job-disables-it.test.ts b/src/cron/service.runs-one-shot-main-job-disables-it.test.ts
index 4854a058e4d..4a0e356fb2d 100644
--- a/src/cron/service.runs-one-shot-main-job-disables-it.test.ts
+++ b/src/cron/service.runs-one-shot-main-job-disables-it.test.ts
@@ -188,6 +188,9 @@ describe("CronService", () => {
       storePath: store.storePath,
       cronEnabled: true,
       log: noopLogger,
+      // Perf: avoid advancing fake timers by 2+ minutes for the busy-heartbeat fallback.
+      wakeNowHeartbeatBusyMaxWaitMs: 1,
+      wakeNowHeartbeatBusyRetryDelayMs: 2,
       enqueueSystemEvent,
       requestHeartbeatNow,
       runHeartbeatOnce,
@@ -229,11 +232,20 @@ describe("CronService", () => {
       status: "skipped" as const,
       reason: "requests-in-flight",
     }));
+    let now = 0;
+    const nowMs = () => {
+      now += 10;
+      return now;
+    };
 
     const cron = new CronService({
       storePath: store.storePath,
       cronEnabled: true,
       log: noopLogger,
+      nowMs,
+      // Perf: avoid advancing fake timers by 2+ minutes for the busy-heartbeat fallback.
+      wakeNowHeartbeatBusyMaxWaitMs: 1,
+      wakeNowHeartbeatBusyRetryDelayMs: 2,
       enqueueSystemEvent,
       requestHeartbeatNow,
       runHeartbeatOnce,
@@ -250,9 +262,7 @@ describe("CronService", () => {
       payload: { kind: "systemEvent", text: "hello" },
     });
 
-    const runPromise = cron.run(job.id, "force");
-    await vi.advanceTimersByTimeAsync(125_000);
-    await runPromise;
+    await cron.run(job.id, "force");
 
     expect(runHeartbeatOnce).toHaveBeenCalled();
     expect(requestHeartbeatNow).toHaveBeenCalled();
diff --git a/src/cron/service/state.ts b/src/cron/service/state.ts
index 4dc1fffdf0a..4faa9f277d8 100644
--- a/src/cron/service/state.ts
+++ b/src/cron/service/state.ts
@@ -38,6 +38,14 @@ export type CronServiceDeps = {
   enqueueSystemEvent: (text: string, opts?: { agentId?: string }) => void;
   requestHeartbeatNow: (opts?: { reason?: string }) => void;
   runHeartbeatOnce?: (opts?: { reason?: string; agentId?: string }) => Promise<HeartbeatRunResult>;
+  /**
+   * WakeMode=now: max time to wait for runHeartbeatOnce to stop returning
+   * { status:"skipped", reason:"requests-in-flight" } before falling back to
+   * requestHeartbeatNow.
+   */
+  wakeNowHeartbeatBusyMaxWaitMs?: number;
+  /** WakeMode=now: delay between runHeartbeatOnce retries while busy. */
+  wakeNowHeartbeatBusyRetryDelayMs?: number;
   runIsolatedAgentJob: (params: { job: CronJob; message: string }) => Promise<{
     status: "ok" | "error" | "skipped";
     summary?: string;
diff --git a/src/cron/service/timer.ts b/src/cron/service/timer.ts
index 913165dcbba..e708a4ea39d 100644
--- a/src/cron/service/timer.ts
+++ b/src/cron/service/timer.ts
@@ -442,7 +442,8 @@ async function executeJobCore(
     if (job.wakeMode === "now" && state.deps.runHeartbeatOnce) {
       const reason = `cron:${job.id}`;
       const delay = (ms: number) => new Promise<void>((resolve) => setTimeout(resolve, ms));
-      const maxWaitMs = 2 * 60_000;
+      const maxWaitMs = state.deps.wakeNowHeartbeatBusyMaxWaitMs ?? 2 * 60_000;
+      const retryDelayMs = state.deps.wakeNowHeartbeatBusyRetryDelayMs ?? 250;
       const waitStartedAt = state.deps.nowMs();
 
       let heartbeatResult: HeartbeatRunResult;
@@ -458,7 +459,7 @@ async function executeJobCore(
           state.deps.requestHeartbeatNow({ reason });
           return { status: "ok", summary: text };
         }
-        await delay(250);
+        await delay(retryDelayMs);
       }
 
       if (heartbeatResult.status === "ran") {