When you stop watering/feeding, the plant will continue to draw moisture from your medium, until....there's not enough moisture in the medium to sustain the plants life. You will know this because the leaves will turn yellow or light green and will start to wilt and curl. This is an indication that the chlorophyll content of those leaves have started to disintegrate (meaning there's no chance to revive the plant even if you try). This is the time to chop, there's barely any moisture left in the plant and its just being maintained by its sucrose/sugar reserve, thus your plant is not bone dry.
The stem will not snap
Good point. I start this process when I'm in my harvest window. If we're talking trichome. I start around 70-80% cloudy regardless of amber or clear trichome. In my experience, 10-15 days doesnt have any dramatic impact on the ripeness of trichome but it does increase trichome production and the calyxes continue to swell.
To your left is the plant at my harvest window (about 8 weeks from flip)
To your right is the plant after dried in the pot
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