diff --git a/scripts/cadence_observer_readback.py b/scripts/cadence_observer_readback.py
index 75d12a3..f2be88d 100644
--- a/scripts/cadence_observer_readback.py
+++ b/scripts/cadence_observer_readback.py
@@ -102,7 +102,7 @@ def sanitize_record(record, source, tenant, instance, event_id, since, until):
     )
     accepted = record["accepted_at"]
     require(
-        stamp(since) <= stamp(accepted) <= stamp(until),
+        stamp(since) <= stamp(accepted) < stamp(until),
         "record_outside_acceptance_window",
     )
     action = record["action"]
diff --git a/tests/test_cadence_observer_readback.py b/tests/test_cadence_observer_readback.py
index 63136a5..4a08987 100644
--- a/tests/test_cadence_observer_readback.py
+++ b/tests/test_cadence_observer_readback.py
@@ -66,6 +66,12 @@ class ReadbackBounds(unittest.TestCase):
         with self.assertRaisesRegex(lane.LaneError, "acceptance_window"):
             self.sanitize(record)
 
+    def test_exact_until_is_excluded_like_receiver_sql(self):
+        record = self.record()
+        record["accepted_at"] = UNTIL
+        with self.assertRaisesRegex(lane.LaneError, "acceptance_window"):
+            self.sanitize(record)
+
     def test_paths_are_bounded_to_exact_approved_coordinates(self):
         result = lane.paths(
             "qonto-assistant",