User blog comment:Xilinoc/Ch. 547 - Peace from Shadows/@comment-1268838-20130904145545/@comment-5657895-20130904193322

I think Aizen will become back too, unfortunately, but he isn't free yet, at least I don't think. Aizen was sealed pretty impressively if it's meant to keep him down there for 20,000 years. I dunno if it would be that simple. And we don't know if everyone from Seireitei was transported or not. Muken itself seems to be a separate, compartment like dimension of the Soul Society. Rukongai wasn't transported, so I don't think everything or everyone is gone.

Besides, even if he was, he would be fodder to the likes of Yhwach.