fix offset aware datetimes
diff --git a/staffeln/conductor/manager.py b/staffeln/conductor/manager.py
index 5b05a62..a8d69a0 100755
--- a/staffeln/conductor/manager.py
+++ b/staffeln/conductor/manager.py
@@ -128,7 +128,7 @@
         report_period_mins = CONF.conductor.report_period

         threshold_strtime = datetime.now() - timedelta(minutes=report_period_mins)

         filters = {

-            "created_at__lt": threshold_strtime,

+            "created_at__lt": threshold_strtime.astimezone(),

             "backup_status": constants.BACKUP_COMPLETED,

         }

         success_tasks = self.controller.get_queues(filters=filters)

@@ -210,7 +210,7 @@
             if backup_age > retention_time:

                 # Backup remain longer than retention, need to purge it.

                 return True

-        elif self.threshold_strtime < backup.created_at:

+        elif self.threshold_strtime.astimezone() < backup.created_at:

             return True

         return False