1. Like others who have shared, no need to flip to 12-12, she is preflowering. I would recommend switching to preflower nutrient schedule.
2. Consider placing the exhaust fan/carbon filter outside of the tent that can create more room at the top of the tent so you can raise your light.
3. Consider bending over the branches that are too close to the lights. Ensure you have a plan on to where to fold each branch as you don't want the branches laying on each other. Squeeze the branch between your fingers, where you want to the bend to be, and then gently fold over. Grow Weed Easily .com has a good article on super cropping -
"Super Cropping Marijuana: Simple Secret to Bigger Yields", you may find useful.
4. Had some extreme stretching with my first grow, ended up needing to attach the light directly to bar, without any pullies, removed the exhaust fan to outside the tent and super cropped the crap out of one plant.
Best of luck to ya!