Not the solution
Certainly, using the constellation for broadband provision would make sense (particularly for those UK households unable to get decent speeds). It is, after all, what it was designed to do.
Given how tiny the UK is, you could easily provide the same service with a few of Google's dirigibles. Satellites are designed for covering large areas of the earth with their signals.
Oh, hang on. Is that the 19:21 Gravy Train? I have to catch that one! If you fine it, mine's the one with "A Short History of Barnard Castle" in the pocket but you can keep that.