diff --git a/tests/test_issue78_reset.py b/tests/test_issue78_reset.py
index dc9b2d2..fe6d3fa 100644
--- a/tests/test_issue78_reset.py
+++ b/tests/test_issue78_reset.py
@@ -1733,15 +1733,19 @@ def test_reset_waits_for_an_admitted_submit_and_sees_its_job(mam_sandbox: Path,
         stderr=subprocess.PIPE,
         text=True,
     )
+    exclusive = "lib_py.pane_lock acquire --fd 7 --wait-env MAM_UPDATE_ADMISSION_WAIT_S"
     try:
         deadline = time.time() + 60
         while time.time() < deadline:
             assert proc.poll() is None, proc.communicate()
-            if any("lib_py.pane_lock acquire --fd 7" in a for a in _descendant_args(proc.pid)):
+            if any(a.endswith(exclusive) for a in _descendant_args(proc.pid)):
                 break
             time.sleep(0.1)
         else:
             pytest.fail("reset.sh never waited for the admission lock")
+        # Still blocked a second later: a shared take would have returned at once
+        time.sleep(1.0)
+        assert any(a.endswith(exclusive) for a in _descendant_args(proc.pid))
         assert not (mam_sandbox / ".mam" / "reset-in-progress").exists()
         assert not (mam_sandbox / ".mam" / "loop-guard-active").exists()
         jobs_dir = mam_sandbox / ".mam" / "jobs"