I brought a copy years ago, it's an interesting read, covering the commercial reality behind the stations.

Then I discovered the Geoff Chapman I know is actually Robert Chapman's brother, and he told me that it's basically Rob's M.A (Master of Arts: an advanced university degree) turned into a book.

Rob is interviewed in this podcast -

https://uk-podcasts.co.uk/podcast/bureau-of-lost-culture/the-lost-world-of-pirate-radio-part-one