I don't remember reading much about this, but it looks like a fairly significant new book. I'm not going into it with great expectations, particularly having heard his interview earlier on the radio, but the author was previously editor of a major pop magazine here in the UK. It's also 544 pages long and he's supposedly conducted 220 "exclusive new interviews", so hopefully there'll be at least a few new angles on things.

https://guardianbookshop.com/prince-a-sign-o-the-times-9781785121944/