2 out of the 4 barneys farm - gorilla skittzl went yellow and red.
I also let my tent get down to around 15c in the last 3 weeks of flower.
If your plants got the genetics for fall colours that will bring them out as well as I crease resin production.
Dont let your tent get that cold if your plants aren't healthy and you don't know what your doing.
Try to keep less than a 10c difference between day and night time temps