Royal Warwickshire Regt, how late could it have been taken?

[High Wood]

This photographic post card was amongst a shoe box full of annotated photographs that I recently purchased. Having researched the names of the family members, I can narrow this image down to one of two people.

The first man was born in 1907 and died in 1931 age 24, if he enlisted at the age of 18, the earliest that the photograph could date from is 1925.

As this man was known to have been a civilian lorry driver involved in a fatal accident in 1930 and was dead by 1931, it cannot date from after 1931.

The second candidate was born in 1920 and, if he enlisted at the age of 18, the photograph cannot be earlier than 1938. As this was about the time that Battle Dress was being introduced, is it possible that a soldier could be issued a tunic of this pattern as late as 1938?

I have the second man's Army number, 5111448, which in relation to another Royal Warwickshire Regiment Army number. 5114466, issued in October 1939, is 3,018 enlistments earlier.

Your thoughts would be welcome.