StillCan'tDance in a private conversation with me around 9 years ago, Paul Russell said that he would not being doing a second book.
Paul basically achieved all that he wanted to with the first book.
That is a shame because he is a gifted writer. However, I can fully understand him not wanting to do another - why write about a period of the band that he doesn't particularly care about? We won't get a better chronicle of the band's live performances up to 1975; Paul's book sails about as close to perfection as it's possible to get.