User blog comment:-Mr·Bubbles/Earth & Water recap/@comment-5242921-20130826181258/@comment-8484378-20130826183037

It's possible, but I don't see how you can title an episode about Finn and Jake getting a sandwich back from Magic Man into Earth & Water, unless it's based around a phrase. But it's still a huge stretch even when compared to most retitled episodes.

But it seems that the September line up was changed in general, so there's a strong likelihood that this is just a new episode.