Hiya... Message for EVERYONE - The ONLY way to make sure you don't lose your Bike entitlement is to request under Freedom of Information Act from DVLA themselves a list of the categories they have listed for you... It costs a fiver but it is well worth it....
DVLA will NOT accep photocopies of old Licences or even certified evidence from Coppers/Courts or anyone else!
You can do it over the phone yourself or send to Freedom of Information D16 DVLA Longview Road Morriston Swansea SA6 7JL
Make sure you get a reply (and info is correct) BEFORE you send your licence back - they have to reply within 10 days.
Good luck... Regards... Roger