When transitioning to DST, the system clock time is advanced by one hour. However, Integration Server will not skip the scheduled tasks that were scheduled to be run during the hour that is skipped because of transitioning to DST. If a task was scheduled to run in the hour that was skipped, Integration Server will run the task in the ensuing hour. For example, if you have scheduled a task to run at 1:30:00 a.m. and if system clock time transitions to DST at 1:00:00 a.m., Integration Server will process the task at 2:30:00 a.m. system clock time.

When transitioning from DST, the system clock time is set back one hour. For a repeating task scheduled to run in the DST overlap, Integration Server does one of the following:

If a task includes an hours mask (e.g., "1:15" for running every date at 0115), then the task will run only once, at the pre-overlap ("first") matching time. For example, if a task is executed at 1:15:00 a.m. and if the system clock time transitions to DST at 2:00:00 a.m., which sets the clock back to 1:00:00 am, Integration Server does not process the task again at 1:15:00 a.m.

If a task does not have an hours mask (e.g., "hh:15", meaning run at 15 minutes past each hour), then the task will run at the pre-overlap time (the "first" 1:15), and also at the overlap time (the "second" 1:15).

The simple and complex repeating tasks are unaffected by the transitions to and from DST. Integration Server processes the repeating tasks at the specified intervals. That is, if a task is scheduled to run every hour, Integration Server will execute the task at hourly intervals regardless of the system clock time.