You're asking if they'll release a volume with all of the 26 episodes they produced in this run despite airing them as two separate runs, or will they just release another set after they air the remaining 13 episodes with just those episodes on it.... so should you buy the dvd set that's out now, or wait for one with 26 episodes on it, correct?
I don't know the answer to that, but I'm guessing that it'll be two separate sets and there won't be a super set with all 26 episodes on it. If you haven't seen the 13 new episodes though, they're really good and the set is a decent purchase as per my opinion.