ES2 Engine Numbers

Can anyone confirm the year of my new ES2

The numbers on the engine and frame the same
40333
4

also has HH127 on the crank case.

It was registered in 1952 but I don't know if it is a 51 or 52.

Thanks

Nice to have matching numbers.
According to Roy Bacon
4 = ES2
42700 approx = the first 1952 calendar year build, so a "51 build, but 1952 model year started Sept '51.
There should also be a letter before the first "4", F to indicate model year 1951, or a letter G for MY 1952 ??