dude they arent done, there is no such thing as a white strain lol
Signs by visual inspection:
1)When pistols are 90-100% receded into bud (they arent reaching for the sky all healthy looking)
2)When 30% or greater pistols turn orange/red/purple/pink/brown/blue
3)When all Calyx have swollen
4) When some fan leaves have a golden tinge
Now check your trichs if you so desire and cut when they are in right phase: All trichs need to be milky at the least but ideally with 10-40% amber. Checking trichs is unnecessary and if 1-4 are true than it is fine to chop