I would take off the lower 1/3 and a few branches that are just too much, than wait about 5-7days and start with 12/12. Like this the plant will grow much better, you can also try to give direction to the branches by pining them down with a threat or smth. The more space branches have the bigger they get and that actually matters a damn lot. Right now your plant has enough leaves to push crazy, but is too centered, try to spread the branches a bit to get all the leaves potential. Regardless i would cut the lower 1/3 half of leaves and branches. leaves you dont really have to cut, but helps to controll your plants via eyes, is better for RH and if you have a fan for your roots/pots (adviseable to do), it betters the airflow.
I like to go for 14hours darkness/10hours light just a few days to speed up the flip into flowering, but thats my broscience, i wouldnt trust in that part.