"Lt. W.B. Sparks of the Highland Light Infantry "A" Company and Capt. H.D. MacFarlane of the 14th Field Company Royal Canadian Infantry atop a dyke awaiting the jump-off to the attack on Leer"
I can see three probably four windproofs in use, the person in the lower left is too blurry to say for sure.
From what I've been told by our Veterans, the Windproofs were issued, however they were issued from the top down (as it was with most shiny pieces of kit, kinda like today), so it took a while for the privates and corporals to get them, however they eventually did.
The examples I have in the Regimental Museum come from a corporal, a sergeant and a lieutenant.