Chris,
As Danny says either no actual donor & built from several cars, possibly DVLA not knowing their arse from their elbow, or I do know somebody who was told if they wanted an age related plate it would take 2 weeks, if they would take a Q plate 30 minutes. But unless you want to put a private plate on it's no biggy for a buggy they are not exactly production cars, might be different if you had a Furrari lookilikey/wannabee & wanted to wear a red jacket down the pub.
Alan...