Yeah you can change or you have to change the light to 12/12 when you want to send the Fem into flower. But you won't get as much out of the Autos when they get 12/12 the rest of the Time as they will give you when they get 18/6 till the end. Automatics perform better when they get 18/6 all the time. Automatics and Fems in one tent is a little bit tricky, it works better when you have a vegetation-tent and a bloom-tent. So yo can move the Fems into the bloom-tent when they are ready and the Automatics will finish in the vegetation-tent, where you can put a new Fem on the way which you can put into the bloom-tent when the first fem is ready