Am i on a harvest window?
77 days old autoflower, up to this point is personal taste or still there ways to go?
I majorly see milky and a few ambers trichomes, correct?
Those white pistils are due to the foxtailing, so is not a good metric.
Yes I would say you are within your window based on your trichomes in the pictures, so now it is just personal preference and thinking if those pictures were from the most mature buds or the average matureness of the plant. Your plant looks good BTW, definitely looks like it's going to be some good smoke!
i'd ignore the few new white pistils and judge based on the bulk of the plant.
trichomes
pistils
density.. use all three for more consistent harvest window timing. Experiement for yourself early to late harvests. drugs impact some brains differently than others. E.g. alcohol sometimes makes people hyper and others lethargic. Nyquil either puts you in a coma or makes you hyper... can't assume it is the same for everyone with THC, either, even if the variation is less common - not saying that's the case but is possible.