All Get Out has been added as support to Fun. for two sold out shows this Friday, in Atlanta, and Saturday, in Nashville, before beginning their tour with Anberlin and Paper Route on Sunday. Full tour dates can be found in the replies.
This seems like a weird pairing even for The Format fans.
I think fun. still considers themselves a "rock" band and they've toured with plenty of other actual rock bands. I saw fun. open for Manchester Orchestra a few years ago, and it worked. This is a total generalization, but from what I've seen, a lot of The Format fans are also fans of Brand New, Thrice, MO, and other bands that more closely resemble a band like All Get Out.