Hey there...so i wouldn't necessarily say that sativa strains take longer to finish, but I know many Haze strains take longer. But that should only be a problem if you're growing outdoors and need them to finish before the frost. I believe the ninja fruit has some haze background. I really wanted to grow some Neville's Haze but it's notoriously long so unless you're in the more southern areas like California or somewhere that has a late late fall season it's a problem.
With your sex hunt I'd just get in there and photo everyday and watch for the preflowers and I'm sure you'll catch any roosters in the hen house in time. ✌️