diff --git a/module/os_handler/mission.py b/module/os_handler/mission.py
index 6ac082454..5207a4dca 100644
--- a/module/os_handler/mission.py
+++ b/module/os_handler/mission.py
@@ -1,3 +1,5 @@
+from datetime import timedelta
+
 from module.base.timer import Timer
 from module.base.utils import *
 from module.config.utils import get_os_next_reset, DEFAULT_TIME
@@ -221,7 +223,12 @@ class MissionHandler(GlobeOperation, ZoneManager):
         next_reset = get_os_next_reset()
         logger.attr('OpsiNextReset', next_reset)
         logger.attr('OpsiExplore', (enable, next_run))
-        if enable and next_run < next_reset:
+        # -12 hours to handle DST
+        # `next_run` might be calculated before DST but it's DST now
+        # 2023-03-14 11:15:28.423 | INFO | [OpsiNextReset] 2023-04-01 03:00:00
+        # 2023-03-14 11:15:28.425 | INFO | [OpsiExplore] (True, datetime.datetime(2023, 4, 1, 2, 0))
+        # 2023-03-14 11:15:28.426 | INFO | OpsiExplore is still running, accept missions only...
+        if enable and next_run < next_reset - timedelta(hours=12):
             logger.info('OpsiExplore is still running, accept missions only. '
                         'Missions will be finished when OpsiExplore visits every zones, '
                         'no need to worry they are left behind.')