Central 46 makes Shunsui the need Head Captain.
Unahana changed her first name to Retsu from Yachiru. Revealing she is the one whom Kenpachi respects.
It's revealed why Shunsui and Ukitake both fear upsetting Unahana. She's the original Kenpachi from 1000 years ago.
Shunsui takes Nano with him to Squad One as a secondary vice captain; needing her to keep him in line, while Old Man Yama's replacement takes care of the official duties.
Central 46 is put in their place by Shunsui, who points out they will die unless they make Kenpachi stronger as one precaution.