I am frustrated because I really wanted to have this done and over with, Finn's a yearling now, but the vet said at this point the best option is to just give him a little more time. It's weird because this is the same vet who was kind of getting after me because I hadn't scheduled Finn's gelding when he was like, 7 months! Finn hasn't shown any signs of maturity or interest in the mares, though I have been separating him into my side yard when Freyja had her foal heat, and Misty is due to come in heat next week so I'll put him up then too. It's not a big deal to keep him away from the girls for now, I guess, I just wanted to get the job done. Bleh.
So for now I'll just keep checking Finn until he's complete, and reschedule the surgery for then, but if he hasn't fully dropped by the fall I'll just have the vet go in after it. I guess this is just more a rant than anything else.