I have an EASA CPL, issued last year on the strength of a restricted JAR Class 1 medical. When I get my next medical, I will be "demoted" to class 2, due to CVD. I am not going to hand my CPL back though. Unless someone tells me otherwise, I will simply treat it as having reverted to PPL privileges only.
I will continue to do paid instruction for PPLs, but will no longer be eligible to teach for CPL or do other aerial work.