can you add JAR ratings to CAA national licences?
This has been possible since Jan 2000. With the exception of the IMC rating and SLMG Class rating, they have been the only ratings you can add to an old CAA licence.
Its interesting to note the contradiction contained in the above CAA reference to the
EASA one where Matthias states on page 4 that their main goal is to ensure pilots do not loose existing privileges!