Well it shouldn't do them much harm, it could stress them for a few days. just don't do this often, work out when you want the lights on, change it, and stick with it. good luck

from my experience, plants don't usualy like to be moved, so taking them outside may be a bad idea, but hey, if you're willing to risk it go for it! why not start a few seedlings off inside, then take them outside for a full outdoor grow?

also by moving the plants during flowering, you may knock crystals off the buds, which you don't want.