Calculate penalty expiration based on event date instead of current date

Author: falbru

lego/apps/users/models.py

@@ -546,16 +546,16 @@ class Penalty(BasisModel):
     objects = UserPenaltyManager()  # type: ignore
 
     def expires(self):
-        dt = Penalty.penalty_offset(self.created_at) - (
-            timezone.now() - self.created_at
+        dt = Penalty.penalty_offset(self.source_event.end_time) - (
+            timezone.now() - self.source_event.end_time
         )
         return dt.days
 
     @property
     def exact_expiration(self):
         """Returns the exact time of expiration"""
-        dt = Penalty.penalty_offset(self.created_at) - (
-            timezone.now() - self.created_at
+        dt = Penalty.penalty_offset(self.source_event.end_time) - (
+            timezone.now() - self.source_event.end_time
         )
         return timezone.now() + dt