Your right you have missed the boat for Britannia, 17 1/2 I believe, but as far as I am aware Monarch take on up to 21 and even over that in certain circumstances although that may have changed recently so I stand to be corrected. Try emailing this address
[email protected], I believe he is in charge of training at Monarch and would be able to give you more up to date info. As for doing the licence I believe Brunel College in Bristol still runs 2 year JAR-66 courses. Give them a try.
Hope this is of help