If someone has 3 hours to spare this is very interesting :
https://www.youtube.com/watch?v=oRKOr_RhdyA
This was played out as a wargame on a potential brexit with former prime ministers, economics, ministers for foreign affairs ect of the EU, sure its just a "play" but the people participating for sure have a little insight on how it maybe will play out now in the conference rooms during the coming negotiations.