recently Kubo was a guest of a Japan show.During that show, he talk about Bleach by answering questions.
And he gave us some major spoil (two) about the future of Bleach and one of them is about Isshin.
Well Kubo already said that he will tell us about Isshin's past and in that show he said that Isshin will have an important role in Bleach story.
He also said that actually we're in the (end of the ?) Arrancar Arc and then there will be another Arc (Royal Guard, VL ?) an after that arc, another one where Isshin will "play" his role.So those who thinks about Bleach end, well we at least will have another two arc and for the one after the Arrancar Arc, Kubo's planning to draw something short-like mini arc.
The second is about the two corpses that Mayuri found in Szayel lab.Kubo said thoses corpses will also have a key role in the story.
Then in bonus, Kubo drew in live during that show for his/Bleach fans.