User blog comment:Fallenbladr/Aizens Escape/@comment-24165551-20140818041131/@comment-4207271-20140820093603

My theory I posted a while ago was that he *didn't* lose his Zanpakuto as he thought. Since the Hogyoku manifests will, Kyoka Suigetsu, being a Zanpakuto, would desire to remain with Aizen, and to make that happen Aizen and Kyoka Suigetsu would have to merge, the possible start of this can be seen when Kyoka Suigetsu is merged with his arm. This would also explain the time delay Yhwach found, as he would still have his powers. Hell, if this is true, he might not even be in the prison, he could be chilling in the palace itself just because he feels like it.