Say Cheese, those girls are looking great! Good work. I would bet you still have 2 weeks left. Go to a nursery to get a 30X magnifier. That will help you see the trichomes. The trichomes will tell you exactly when to harvest, not your red hairs. The red hairs just kind of tell you to keep an eye on them at this point. Once you have about 25-50 percent amber trichomes (which is the way to tell your weed is ready) and the other 50-75 percent will be cloudy, not clear. That is when to harvest. Most strains take from 7 weeks (at earliest) to 12 weeks at latest.
My guess is that your girls look very happy and healthy, and will be done at 8 weeks or so. Keep up the quality, it looks great!