If you can fit all the pots under one light, then by all means turn the other one off for now. 2k is probably a bit wasteful for plants that small, unless you need the second light for even spread. Either way, it doesn't matter too much unless it is affecting temps, so it's your call.
If I was in your position, I wouldn't transplant just yet. Those plants are still pretty small, and there is still plenty of root space available. Added to this is the fact that you watered them yesterday, so at the very least you should wait until they are due their next watering. If you drenched them yesterday, and then drench them again today to water them into the new pots, that would be considered overwatering.
I would leave them at least a week, but at the very least, leave them until the next time they feel light.