This plant should have been close to harvest ..
Autos LIKE one light schedule thru harvest .... 18/6 or 24/0 or even 20/4
Autos on 12/12 from " start " tend to be smaller in growth .... Because .. Veg stage is SHORT to begin with ( genetics ) it moves to flowering faster but hasn't been allowed to utilize the longer light and " energy " it gets from MORE LIGHT.
But ...... There is a workaround ... Which i do on mine.
I grow out auto with as much light as possible thru PREFLOWER ... THEN i flip 12/12 for flower. It helps with temps during day ( because lights are off sooner / cooler ).
Your schedule seems to indicate you CHANGED cycle in the middle of flower.
60 days ... It should have been flowering already. ( 30 days from seed - veg to preflower )
Which leaves about 30 days in BEFORE you flipped ... That kind of stress will create hermies ... Autos will seed also when it senses its endlife as to save its lineage. I have run strains beyond estimates and was blessed with fem seeds ( ice bomb ) which to me is a win.
Plus most AUTOS finish at or near 100 days anyways
( 4-5 weeks seed to veg / preflower ) = day 35 or so
( breeder flowering times 8-9 weeks average = 60 days or so ACTUAL flowering time )
Total ( Day 95 + or - )
There are some short time strains ... 60 day wonder , short ryder , etc.
But all would be according to triches to determine harvest.