Avenger, as long as the UK follows EASA rules, you are probably right. But as far as traffic rights are concerned they, and EU airlines such as FR, are up sh*t creek without a canoe.
At best they will get a EU-Swiss model. Unlimited 1st to 5ths, but no 7ths to 9ths. In other words, every FR flight UK - EU is going to have to originate in Ireland and vv.