I originally had a U.K. ATPL in 1994 which became a U.K. JAA ATPL then eventually
a U.K. issued EASA ATPL, then last year I added an SEP related rating, and the license came back as a U.K. part FCL ATPL.
If I was putting it on a CV I would just say it was a U.K. ATPL. Which in reality is what it always has been.