I see the article continues to refer to the registration date rather than the manufactured date which is what is enshrined in the legislation these simplified 'guides' issued by the nudge unit can be a mine field how can we or a copper get to the finer points without a lot of hasselUK people would be wise to read this - effective 20 May 18.
https://www.gov.uk/government/news/mot-changes-20-may-2018
And then scroll down to the pic of a primrose coloured car headlight and click on 'substantially changed' (2 lines below the pic) to see all the rules. Some of it excludes motorcycles - but as anticipated - it's not clear what is relevant and what isn't....
Peter B