wow that looks nice, i always wait until the hairs are about 70-80 percent brown, then flush them with just water for a week, by the way what strain is that??
just my somewhat uneducated opinion, but i've begun suscribing to the belief that when they are done, they just have this certain look about them, this ripeness, and i would say those are ready.
i had a plant that look like that before, but mines showed least green then you. Thats outdoor in the cold for a few wks. Just chop it down they won't get any better. GL!
looking great. i would say they are almost ther if not there already. check the trichs with a magnifier and see if you have some amber. if so then you could pull them now or wait a week. late