a particulars / tax book question

a particulars / tax book question

Not sure is this the right section but here goes my frame number and engine number for my bike suggest it was manufactured in 1989 – feb 1990 but is registered as a 1992 i know this isnt a huge deal but i would like the 89-90 plate because it would bring the bike closer to the 30 year old mark. Has anyone here had similar issue and is it more hassle than its worth trying to get the 2-3 years onto its age
Source: a particulars / tax book question