Various channels went off air tonight on multiple TV platforms for varying amounts of time. Affected the likes of Channel 4, More 4, Channel 5, S4C and others apparently.
C4 HD was definitely affected on Virgin Media as my recording of
Bettany Hughes' Treasures of the World recorded a static screen for much of it. I'm watching it on VM Catch-up as I type this as a result.
https://www.bbc.co.uk/news/entertainment-arts-58694894