User blog comment:Xilinoc/Ch. 573 (Let Unohana return plz)/@comment-3507581-20140320001311/@comment-5398287-20140320011428

Well, confirmed as in someone actually said it happened, rather than just Unohana saying "oh I think I'll die now okay bye". Admittedly, the same thing happened with Byakuya, and as I pointed out there's still some ways of her being alive.