My guess is 1937. That would make him 65 and her 51. She looks older than 51 and he looks younger than 65: 1937 is a bit of a compromise guess. The uniform makes it more likely to be 1939. Are you sure about those birth dates?
The collars were not allowed to be open on those uniforms until late 1944.
My grandfather was born in 1877, my grandmother in 1884, and my dad in 1924, and he married in 1945, and I came along in 1968...so the dates are odd but not impossible! It is such that I am the only serving soldier with a grandfather that served in South Africa for the whole of the 2nd Boer War....
