Yea a crappy time of year to grow with low rh, I found humidifiers make things worse, and plants grow slower and have to fight through it, that said my dark devel plant is doing OK, this pheno does not have the black leaves at least yet, in med pre flower and good health still growing vertical, when I flower it ill cut the cycle to 12/12 as long as you're auto is clearly female this will help, plant went through it's stretch and will just leave in veg till it stops growing vertical and is in heavy pre flower till I remove from tent and flower it., big devel not so big but again is clearly female so cutting the cycle might help plant flower or may not, a free seed that were bought in 2017 but plant does not seem to want to start to flower, will water and feed later today and post pics, plant clearly female in good health but you do not add flower agent you put under booster and cut cycle and see if it starts to flower sometimes they do sometimes they messed up the cross and it won't, I'm a lot less concerned with dark devel bc it is in med preflower and still growing vertical but we will see.