IMO you should be fine. By the time you are done getting them to show preflowers, the days are going to be even longer.Just don't mess around, once you are sure of the sex, get them back outside. The worst that could happen is an early harvest if they don't reveg.
Right now I've got 5 females I'm going to use for clone moms,one just finished budding and got chopped x-cept a few lower branches and small buds, she has been back at 24/0 lights for 4 days now and is already showing new growth.The other four started at 12/12 from seed, they were showing sex after 3 weeks of germinating.I kept two of the best from two strains and put them at 24/0 and topped them 4 days ago, and all is very well.I still have one female at 12/12 just to see how it will do from seed straight through 12/12. So, as I said, IMO you should be fine.