Have you been top watering every once in awhile?
My Auto Tent #1 Diary is 3 Fast Buds Blackberry Auto that I was using a SIP system. SIP is bottom watering, kind of like Auto Pots.
When I got to flower, my leaves started looking like yours.
I was not supplementing with top watering enough and my roots didn't fill out the top of the pot because bottom watering systems only wet the bottom 1/3 of the pot. The roots searched out the water from below and because I wasn't top watering enough, they actually grew down into the bases.
I removed the roots, stopped using the bases and started top watering.
Issue went away but if I let the pot dry out even a little to much, the issue starts to show again.
It was pretty much root bound systems, your roots may not be growing out the bottom but if you haven't been top watering enough in addition to the bottom watering then your roots may not have filled out the top as they should of.