Thanks for your replies! I have all of the flying requirements completed and there is (or as is now the case WAS) a possibility my examiner and I would miss each other by the revalidation date so I wondered if it was possible to miss out by a couple ofweeks and then get it all signed restrospectively and back dated. I've had conflicting advice on this.
I assume that the license has to be signed by the renewal date but the paperwork to the CAA can follow up to a few days after seeing as you can get right up to the revalidation date to get it all done.
Which then begs the question .... how do the CAA know what date it was signed????