No! - Most Autos are done in 10-12 weeks? (70-90 days) Ive only had 1 huge Sativa Auto go 14 Weeks in 5 Years. I have never had to flip to a 12/12 Cycle to flower an Auto. I've Run a Perpetual Auto Tent since 2019 - I plant and harvest my Auto tent every 6 weeks. By the looks of your Plants they are "just starting to set fruit"(stacking). If you had to flip 12/12 to flower them they are not Autos. The Chlorosis (yellowing/early fade) indicate a lack of nutrition, specifically not enough Nitrogen in the soil to go through the stretch.(she is pulling nitrogen from her leaves). Prior to the 12/12 flip always feed heavy "Veg formula", as stretch is the "last big push of the Veg Cycle", Nitrogen = Energy, and it takes a lot of energy to grow 10-15" in the stretch.
Ive heard a lot of People getting Photoperiod strains from Mephisto marked as Autos? Unfortunately you will lose a lot of those leaves...If you hit her too hard with "Only Nitrogen" now it will be a detriment in Flower. What are you feeding? I would increase her nutrients 25% to start with(50/50 blend of grow/bloom formula , and do it now. good luck, Right On!