Well I have a poo-brown non-expiring CAA licence dating from 1978. It seems if I wish to convert to one of those EASA thingies I have to prove my competence in using the English language, despite all my tests, checkouts, biennials etc etc since my first flying lesson being conducted in that language. Oh, and my RT licence, the test for which I passed in 1978, and was conducted by a Manchester ATCO was also (surprise surprise) conducted in English.
I understand if I do not convert to EASA I cannot fly the likes of the Cessnas and things I did my PPL on all those decades ago. I can still fly the likes of Chipmunks and Yaks though, so that's all right!