Hey, buddy! Yes, it's time to switch the lighting to 12/12. Keep in mind that after the switch, the plant will start stretching (active upward growth) for about 3 weeks and will increase in height by +140%. So, if before the switch it was, for example, 40 centimeters tall, then 3 weeks after the switch and the start of pre-flowering, it will be 40+140%=96 centimeters. Good luck, buddy! 👋😊