Keeping an auto in the dark for 48 hours before harvest is supposed to boost resin, but nothing I have measured or tasted backs that up. The plant is mostly done by that point, and two days without light just means two days of no photosynthesis on a schedule that is already tight. The myth versus evidence page on
https://turboautoflowerseeds.com
goes through the common pre harvest tricks and rates the support for each one. I chop in the morning at lights on and leave it at that.
