This read-write object enables Daylight Saving Time on the switch either as an annually fixed schedule or a recurring rule-based schedule, or disables it entirely, with the description noting that switching to repeating or annual resets the other DST objects to defaults. An administrator sets this according to the local region's DST observance rules before configuring the specific start/end date objects. For example, an operator in a region using fixed calendar dates for DST would choose annual(3) rather than repeating(2), which uses week-and-day-of-week rules instead.