Thank you Mitch, that's great and useful info. And these I'm sprouting are F2 so.........I'm excited!
It depends the strain and genetic combination, we never saw males in an f1 generation for a long time, until recently, the sour livers and livers x auto blues f1 put a few out.
It's pretty simple, at f1 or f2 you'll see them starting to flower whilst on 24/0 lighting regime whilst everything else (non auto) keeps on vegging like a normal photoperiod would
In the f2 generation this is perfect and those are the ones you're looking for.
At f1, those aren't the ones I'm looking for as it seems the auto trait is too strong whereas it should be recessive , and we are looking for the specimines most like their photoperiod parents to work with.
Cheers