Changing light schedule 1 hour back because of DST?

I'm not really too concerned but I like having my lights come on at noon so I can check on em earlier and start working on them earlier, plus I go to class at 2 on MWF. Anyways, I am not one to make small changes which bring large negative results. I'm not sure if one hour of schedule change is enough stress on the plants to do any significant damage. My timer works in 30 min intervals, so I could also set it back 30 min tonight and 30 min tomorrow night for a total of a 1 hour setback.