diff --git a/tests/test_e2e_v27.py b/tests/test_e2e_v27.py
index 8927f2d..ac968ba 100644
--- a/tests/test_e2e_v27.py
+++ b/tests/test_e2e_v27.py
@@ -1072,12 +1072,12 @@ class TestE10FullChain:
             f"子任务未被调度！{MAX_WAIT_AGENT}s后仍为pending"
         )
 
-        # 4. 等待父状态聚合（1个tick）
-        time.sleep(35)  # 等1个tick
-        parent_resp = http_requests.get(
-            f"{API_BASE}/api/projects/{pid}/tasks/{parent_id}", timeout=10
+        # 4. 轮询父任务状态变化（等待Ticker聚合）
+        parent_result = self._poll_task(
+            pid, parent_id, timeout=MAX_WAIT_DISPATCH,
+            terminal_states=("working", "review", "done", "failed"),
         )
-        parent_data = parent_resp.json()
+        parent_data = parent_result
         print(f"   父任务状态: {parent_data.get('status')}")
 
         # 5. 验证 Stage 进度