There is another card for him, but I can only see it on National Archives.
It is for the Military Medal Award alluded to on this MIC.
This card is for the award of the British War & Victory Medals.
He first saw overseas service some time in 1916 with the 8th Battalion London Regiment.
At sometime he transferred to the 17th Battalion.
The six figure numbers were issued in early 1917. As his MM appears to be inscribed 8th Bn, but the card is in the later number, I would guess he transferred some time in 1917.
http://www.1914-1918.net/london.htm for the London Regiment.
He should be listed in the London Gazette, but there are no citations for the MM.
Phil