CCO O'Brien in today's edition of German broadsheet Süddeutsche: Ryanair has worked out a "Plan B" that will be implemented in September 2018 should no robust Brexit aviation agreement be in place at that point. It would see up to 85 UK based aircraft moved to EU bases. Findling work for them is apparently no problem for Ryanair as Boeing cannot deliver aircraft at the rate Ryanair needs additional capacity. No talk about a Ryanair UK. Rest of the article mainly about Ryanair in Germany (scaling down of Hahn not because of Frankfurt, but Luxemburg, keep Tegel open, let airberlin die, Germany grossly underserved because of Lufthansa).
The article is by Jens Flottau, one of Europe's most respected aviation journalists.