Probably a regular battalion of the West Riding Regiment on the Western Front, autumn 1917.
The guard changes over outside the battalion headquarters. The battalion sports including "a cuddy fight" (wrestling while being carried on another man's back) and "a reveille race" of dressing in full kit before running. The medical officer gives one company a foot inspection. Pack transport mules take supplies to the headquarters (a large house). The battalion marches, led by its band, down a road.