Sorry about wordy confusion. Yes, I don't trust an auto that flowers before 30 days, because I figure it won't produce much. If it flowers after day 30 I feel like it will probably be big enough to be worth the effort to grow.
My last Auto, Purple Amnesia Haze, had pistils on day 21 from sprout, if I remember correctly I harvested around 8 ounces give or take off that one. You just never know what you're gonna get with an auto. That Cherry Bomb Auto vegged for close to 45 days and yielded about the same, but she was an unruly beast that did whatever she wanted, just like my preteen...