42-code which years?

[byf43]

Hello. I've just seen a picture that makes me wonder. It's a 1938 P08 with a 42 code toggle.

I've always thought that 42 code P08's were only 1939 (latter part of year), 1940 and 1941 (first part of year)? Were there any 1938 42 code!? I always thought a 1938 would have the S/42 code?