"I thought to revaildate your licence...."
No, it is your SEP Class Rating which must be re-validated, not your licence.
".., you must have completed 11 hours flight experience as P1 within the second year and an hour flight with a flying instructor, who signs your log book."
No, in the second 12 month period it is 12 hours flying of which 1 must be a Training Flight with a FI and 6 must be as PIC, including 12 take-offs and landings.
"After which you can hand in your log book to be signed at a maximum of 3 months prior to expiry date."
No, the only log book signature required is that from the instructor who conducts the Training Flight. It is the Ratings - Certificate of Revalidation page in your licence which must be signed by the FE to whom you submit your LST/LPC SPA/MPA Form (SRG\1119).
This is right. No it isn't.
The issue in question is the CAA's incorrect interpretation of JAR-FCL 1 in requiring the FE's signatures within 3 months of the expiry date irrespective of when you actually completed the re-validation requirements. If you were to complete these requirements in the first month of the second 12 month period, why on earth should you have to wait another 8 months for a scribble on a couple of pieces of paper?