Small update for others in the same boat.
The UK CAA do not an answer to the question "will my UK National Exam Passes still be recognised by EASA?".
I have been advised to contact EASA direct for an answer to this.
Despite 2 emails I have had no response so have now copied UK MEPs in too.
I guess that formally writing is the way forward now as well as an MP Surgery visit.
Incidentally this all started because I was told by a UK Ground School that my UK National ATPL exam passes were "null & void" and that I would have to "do the entire ATPL Ground School again".
I may vote UKIP next time...........