Any length of abnormal extended darkness will just cause your plants metabolism to slow down remarkably and no doubt stress her. The last thing you want is to harvest a stressed plant after weeks/months of careful growing. The slowed metabolism will probably also lead to trichome degradation and not enhancement, and this technique of extended darkness is an urban myth, created by someone who does not understand how plants function.
My advice is not to do it. Just harvest your plant as she is normally living and about an hour or two after the lights come on. I arrived at this harvest window by doing many experiments over the last three decades as to which produces the tastiest flowers and it works for me, with seemingly the most terpenes and healthiest trichomes.
If all of the pistils are brown, this will mean that the THC is breaking down into CBD and CBN rapidly, and will give you a sedating CBD body stone. If there are about 95-98% brown pistils, this will give you a mind trippy THC head high. So it depends on which effect you prefer as to when you harvest. Deciding on harvest ripeness by trichome colour only is flawed, pistil colour will reflect the plants health and maturity more precisely and it is plant health and maturity that effects trichome structure/composition, not trichome colour. The brown trichomes have degraded THC, which has turned into CBD and CBN, meaning the effect is more couch locking, and not as trippy as flowers with mostly clear or cloudy trichomes. The more amber, the more sleepy/sedating the flowers will be. Don't worry about the bud smelling fetish, I think everyone on this site share the same condition!
Hope this helps,.........
Organoman.