When registering an imported vehicle, the registration document is required together with a Certificate of Conformity. The vehicle must be put through an MOT a.s.a.p., if eligible (Over 3 years old) and the VIN is used and written on the MOT. All the documentation is then sent/taken to the DVLA/local VRO and a couple of days later a U.K. reg.no. is issued which allows the plates to be made and fitted. A replacement MOT cert. is sent from the DVLA showing the reg. no. which shows the original date of registration.
When we moved back to the UK from Ireland, we bought our Irish registered Mitsubishi Colt over which had an "06" Irish plate. The DVLA gave us a "56" reg.no. and the V5 showed the date of first registration being the same as that on the Irish Registration document. The DVLA kept the Irish document.
Personally, I smell a rat with this listing, the VIN should give confirmation of the D.O.B.