diff --git a/sekoia_automation/checkpoint.py b/sekoia_automation/checkpoint.py
index 49126ef..e83e4b0 100644
--- a/sekoia_automation/checkpoint.py
+++ b/sekoia_automation/checkpoint.py
@@ -182,7 +182,7 @@ def from_datetime(self, dt) -> int:
 
     def to_datetime(self, rp: float | int) -> datetime:
         # timestamp -> inner representation
-        return datetime.fromtimestamp(rp / self.multiplier).replace(tzinfo=timezone.utc)
+        return datetime.fromtimestamp(rp / self.multiplier).astimezone(timezone.utc)
 
 
 class CheckpointCursor(Checkpoint):