It is indeed a wedding photograph and I suspect that it is a uniform that was made to look at bit more special for the occasion. I have another photo of him (attached) where he is wearing a normal looking army uniform without the puttees and peaked cap. My husband did mention that he thought it was a specialised mounted (horse) artillery uniform but his period is Napoleonic so he suggested I ask better experts on here

I agree that Catherine looks like she is wearing 1930s garb.
More info on this couple:
Wilf was born in 1918. I've found their wedding date (this morning) to be circa Dec 1939 in Yorkshire.
Thanks everyone for taking the time to reply.