Yes it's easy.
Medical
Fill in the online medical declaration on the CAA website.
Go to your local flying school for training as required followed by a test (basically a mini skills test compared to your initial PPL skills test)
As your licence is valid for life the examiner then signs a ratings page (they should have one if you don't) and you are good to go flying.
No fees or sending anything off to the CAA.
If you want to get a european licence at a later date you can use this licence to do so. But there are a few other hoops to jump through and money to fork out.
Last edited by Mickey Kaye; 10th Jul 2018 at 17:25.