Really looks like a reveg on some. Do you have your tent in a light room or maybe timer is screwy and gives different light and dark times. I had a timer that would stick when it was supposed to go off then it would go off a few hours late. Was a digital timer. I went back to industrial timers. For the burn spots do you spray water by chance? Light burns through the droplets. But it could be advanced root issues as well, do you water to waiste or just water to moisture, some ferts build up in the soil and becomes more than the plant can handle if they don't get a good flush from time to time. Depending on the brand of nutes you use and your grow medium.