Just found the reply the CAA sent me............
Thank you for your enquiry of 4 March 2002, please accept my apologies for the delay in replying.
As you suggest, the examiner who endorsed the new Certificate of Revalidation (C of R) in your licence should have completed a form SPA LPC (single-pilot aeroplane, licensing proficiency check) and submitted it to this office - the form allows for revalidation by experience.
You are also correct in identifying the fact that, provided the examiner signs up the Certificate of Revalidation page within the 12 months prior to the expiry of the current Certificate, the revalidated rating will run from the date the existing rating expires, even if the current rating has more than 3 months to run. (this does not apply if revalidation was by proficiency check).
As we do not seem to have received any paperwork from the examiner, I suggest the best course of action is to get another C of R signed up by your flying club to run from 27/5/02.
Cheers
EA