Good point, but that's actually why I'm planning to do it in the UK (the CAA is my "Competent Authority" FWIW).

It's amazing how involved this cross-national stuff is even within two EASA countries, let alone between two ICAO countries. But a few years living in one country and having licenses from others do wonders to get rid of this kind of naivety. ^_^

AFAIK you can still add a rating via the conversion route & grandfather it on to an EASA licence. An AOPA/BAeA course or any of the other methods outlined in CAP 804 should be acceptable to the CAA.

Which CAA? UK, yes. But not to all the other European CAA's, as the original question was. Some might accept it, some not.

My suggestion where to do it if you want great training is with Alan Cassidy at White Waltham / WLAC: Aerobatic Training, Pitts Training, Aerobatic School
Have done a week-long BAeA/AOPA course with him on a Pitts and it was great. Just as good as his book. You need to find someone who great at 2 things: their own aerobatic flying, but also being a great teacher. Many are former, few are latter at the same time as well. Could not had a better teacher than Alan.

White Waltham is also a great place being close to Heathrow when coming from abroad.

That said, I am still waiting to see if the Estonian CAA will accept the course to issue the FCL.800 proficiency, as WLAC although an ATO does not have aerobatic training on it's certificate. You can argue, if that is needed or not, at the end of the day it depends on the people and regulations in your local CAA.

Eh?? The OP pointed out in the post previous to mine that the UK CAA was his "competent authority."

Skytrek flying school Rochester Kent, operator a C152 Aerobat at £178. In open airspace so real value for money. Instructors have lots of Aero experience and get most people up to speed within 5-8 hrs.

Sounds good MRDAX, thanks for the hint. Though it seems that their Aerobat is unavailable currently (web page says it's "offline").