they look great, but they are still pretty young.. i think that even if you change the light schedule to 12/12 too early, the plants wil still take as much time to show flower as they would have if you would have let them get much bigger in a vegetive growth stage.. it takes plant time to reach maturity, and forcing them into flower earlier really doesn't speed up the process much..
just give em some time.. i had vegged my plants for like 7 weeks or so, and just put them in flower two days ago, and i can only spot sex on the one so far, female, but the other four still aren't showing many signs of sexing themselves..
the good news is that males tend to show sex earlier, so that by not showing themselves too quickly may mean that you have some females..
keep up the good work, and remember to be patient with them..