Pull when trichomes are ready, which I'm willing to bet will occur past day 60. They will keep getting fatter and fatter until they are perfectly ripe. Your quality and yield will be much better.
Day number 48 of flowering. So far growing in a tent outdoors in winter is working. our temps have been in the mid-70s during the day in the high 30s at night. with the lights on only at night it's keeping them nice and warm. Daytime temp is perfect. Getting really close to harvest time!