Yep ...
Stalled .
Autos can do all kinds of shit .... Drop light cycle .... 12/12 to FORCE it to flower.
Even 10/14. And leave it there ... it Vegged plenty up to this point .
LST it ... treat it like a photo seed.
Autos occasionally need a kick in the pants , as some have shown photoseed like trait.
Or it could have been a regular seed.