hello jap2020.most auto`s will flower whatever light cycle you put it on.on 12/12 you will probably just get a smaller yield than you would on 18/6 or more.i havnt grown any under 12/12 lights,so it would be interesting 2 see what kind of yield you get,compared with what the seed co.says it will produce.try and sort yer lights out tho,light is life 2 plants and obviously your yield will be bigger with more.can you keep me posted on the results if you keep lights at 12/12,i am thinking of growing regular along with auto`s. so at some point the auto`s will be on 12/12 light.i believe it tightens the buds up.i will keep an eye out 4 your thread,and results.good luck with your grow.