How about some dates and places Sarah
Upavon is in an area where there was, and still is, quite a large service presence.
Does it say what his occupation was on the marriage certificate, and does it give any more of an address that Upavon? If you can scan relevant parts of the certificates it may help. If he married after 1945/1946, he may have been demobbed and elected to stay in the UK. It is also possible that he may have returned to the UK from Canada after demob.
If he enlisted in a "local" Canadian regiment it may make it easier to track down any details of him.
Paul.