I'be got a short rider plant that's about 6 weeks old now, 14 inches tall. I switched it to 12/12 a week ago and it's now got some preflowers on it. Should I switch the light back up to 24/0 or 20/4, or leave it at 12/12? I expected to be close to harvest time by now, but I think I was just under feeding for too long. Any advice?