Thanks for that insight, Ken.
You are right that he turned out to be difficult to track. His medals and payroll numbers were different - even with a little time at Kew many years ago I couldn't get the story.
I have some papers and army currency stamped "Lille" so know he was in Northern France sometime. Like many, he never spoke of his time in the trenches, and the only story my grandmother related was that he lost his signet ring in a trench during an advance, but apparently found it in the mud again some days later on retreat.
He survived the war with a shrapnel wound in the foot. The irony was that this injury killed him through septicemia in 1939 just before WW2. My father was just 7.