from 1st January 2015 when you renew your uk licence for what ever reason you will only receive the plastic bit back licence no paper bit check your licence when you get it back to make sure they haven't removed your bike licence or other things take a photo of your old licence before you send it off
I lost my original paper only licence and renewed to a photo one as they are accepted on the continent. I later found the paper one which is in the family history album and would be proof, being origianal paperwork issued by the dvla. I realise that many people did not have this opportunity but those who still have paper only licences may try this when it comes to renewal.
Whilst photocopies may not be proof, original paperwork should be more acceptable, unfortunately the new licence paperwork does not have your entitlements on, so it may be worth hanging on to the Plastic section of the old one..... Oops! it fell out of my pocket into a bonfire, got blown out of my hand on a busy motorway etc. may be the way to go as I have heard of others suddenly losing their motorcycle entitlement due to DVLA errors.