A few years back I put a document together as an assessment on the impact on daylight savings time changes. The assumption was that the Daylight Saving Time (DST) time changes take place at 2:00 AM and do not impact activities that occur at midnight. Normal business activities are conducted and no tools such as DCA Autoloader (or other load tools) are being used. Task controller and service tasks are active. Syncade has been updated since this was put together but it provides a great starting point.
Syncade Daylight Savings Time Considerations