Yes, you would! You'd just have to move all the info to that account then resubmit him. I did it in the past in the move to this account and my characters were accepted! Just send a join request as you did with him before.
If you're asking about warrior positions, then most definitely, yes! If you meant high ranks, all that's really left to fill are Steads but there's not much been said about the rank by higher admins yet, so I'd wait on Steads.
Just be sure to read the availabilities on the page before picking your first clan c: UmbreClan could really use some more cats, but you can make another cat free too!