Brexit

Brexit was something which the youth of 2016 considered to be unstoppable. (PROSE: What She Does Next Will Astound You)

Behind the scenes
Brexit is the United Kingdom's exit from the European Union.

Remembrance provides a parody of Brexit in the form of the planet Britzit-247. The part of Britzit-247 seen in Remembrance is a city with elements reminiscent of London which is populated by individuals who all resemble angry Nigel Farages and only say the word "Britzit". There's also a giant robot with the face of Boris Johnson. The Eleventh Doctor explains that Britzit-247 was founded by a group of British who "got cross about something or other" and decided to "travel across the stars" to start their own independent colony.

In the DWU, the UK is still explicitly part of the European Union in AUDIO: The Longest Night, when the British Prime Minister signs the Euro-Combine treaty. Even in this storyline, though, many see the strengthening of the "European superpower" as a threat to the UK's independence.

The UK later belongs to the Eurozone in AUDIO: Hothouse and PROSE: Trading Futures; Trading Futures remains vague as to when exactly it's set, but the after-credits segment of Hothouse places it before the events of The Eight Truths in 2015.