User blog comment:Mrlmm0605/Let's Talk Bleach! Part 15b: Zangetsu/@comment-11446176-20160516093445/@comment-23887466-20160516100246

TBH I am interested about the idea presented by Byakuya after witnessing Zaraki's zanpakutou, that there is no such thing as constantly released zanpakutou. If this can be applied to Ichigo, then we are waiting for a shikai and a bankai maybe.