Have you gotten your light cycle back in order yet?
One day of prolonged light shouldn't cause them to flip back to veg. At day 9 of flower, the hormones should still be adjusting to the flip to flower so you should be good. I would account for a few extra days at the end of flower though, seeing as all that light hiccup should do is extended the hormone adjustment period.
I recommend any sort of outdoor 10amp timer. I don't have any particular brands for you off the top of my head but I would assume there's a good one to be had at your local hardware store. Also. I would get an extra because...life. Lol
Clones are looking good man. From what I've read you could have probably cut off a bit more leafage to limit photosynthesis and upward growth but there's more than one way to skin a cat. I also have not in tried this in practice so someone else should probably chime in.