Some good advice on when flowering that I've found from some grow books:
Most growers are anxious on getting their hands on their juicy bud, but look at the trichomes. When you think their ready, give them about another week to fully amber up.
Also, let them sit in dark four about 24-48 hours before putting light back on them. The darkness represents the changing seasons in nature. As the light during the day reduces more and more, the plant pushes out more THC covered trichomes to help with collecting pollen, also protecting the "seeds" inside from foreign invasions.
I had a friend put his plant in darkness for an entire week and stopped watering it for the week too, and his plants were COVERED in little crystals. Just a lil smoke for thought
Great grow man!! can't wait to see how much you get!