Oh man, what do I think? Dude, I'm slightly off my rocker. If I could find a 48-hour timer, I would say 35/13. But, I can't. Maybe I'm just not looking hard enough. Oh man, there is a way to do it with a 7-day timer and reprogramming it once a week, but f' it.
Now seriously, I looked at Big Bangs stats. Based off this:
Flowering= 8 weeks
Lineage= NL=Indica, El Nino=India/Sativa, Skunk#1=Sative/Indica
Self Classification= Indica/Sativa
12/12
As for the variable of the other plant, what is it? I don't like unknowns.
24/0 Is pretty intense. Not something I recommend. But these plants can handle all kinds. A widely used practice is to gradually shift the light schedule to bloom as opposed to flipping the switch to 12/12 over-night. Just flip it to 12/12 whenever. 11.5/12.5 maybe? Just so you can fight off the paranoia that 12/12 is just too obvious.
Edit: 11/13 I bet it flowers in that.