Originally Posted by zaphod_b
However.. any plate that was legal at the time it was made is also still legal. however if it gets damaged you are required to repalce it with a modern one.. (becuse the ANPR systems have issues with reading the older fonts they would rather you did not repalce like with like). The old sliver on black plates are the worst for ANPR, however if your car is not a '73 or earlier it's illegeal to fit them. Even the pre 2000 plates have issues with ANPR. It was also dues to ANPR that the last few years of prefix plates were change form running a whole year to being 6 months as the current style by their nature are far easier for ANPR systesm
While this is generally correct, replacement number plates only have to be to the current specification for cars registered from 1 Jan 1973 onwards. Also, for MoT purposes the plate will pass if it is compliant with the regulations in force at the time the car was registered, as they have no way of telling when the plate was made/fitted to the car.