Ah, now I see where the issue might be!
in its Notice to Stakeholders, EASA appears to have a different opinion, saying that such licences "will no longer be valid"
I think you misunderstood what the document is saying. UK licences are and
will be ICAO compliant - recognised and accepted among all ICAO members (ie nothing can stop you flying a G- reg aircraft to keep it in simple terms). No one is denying it and nowhere I can find a statement that refutes it; and certainly neither EASA nor the EU would be able to as it is well outside their jurisdiction!
However saying [EASA UK issued licences]
“will no longer be valid” is actually correct because it means “no longer valid
within the EASA regulation framework” for mutual recognition, acceptance of training and all privileges associated with membership. This is what they mean; certainly it is the way the way my workplace and I understand it.
Hence why easyJet EU based crews are getting their EASA licence transferred to Austria (flying OE- reg aircraft) and UK based crews keeping their EASA UK issued licences/maybe soon to be National licences (flying G- reg aircraft).
Again, as has been pointed out and regardless of the rights and wrongs of it, EASA would look pretty stupid if they turned around one day and said we non-longer recognise a certificate that was obtained under our rules ‘just because we don’t want to”.
why?
without a legal framework (call it a deal or agreement or whatever you fancy) between EASA and the UK CAA, it would be foolish and quite frankly arrogant to think mutual recognition will continue after 29th March. On what legal basis? “Just because a licence
was obtained under EASA” doesn’t mean anything, especially as future regulations might diverge between the two parties. You leave a club, you also give up membership privileges.