I don't think it will make mch difference for the autos. It would definitely be more convenient since you have photos in there too. If you're worried about it, you could likely go to 13/11 and get an extra hour.
12/12 should be plenty of light though. Just go easy on the autos, stress and shock is a bigger threat to your yield than not getting enough light at 12/12.
This is just intuition though, wait and get a concensus or an opinion from someone well respected on this site.