Pte 8282 Arthur Cook 4th Royal Fusiliers went Overseas per MIC on 21 December 1914 from that I assumed he must have been Trained and in the Army pre War
I have since found Near Numbers to 8282 were :-
8279 Henry Carter Enlisted 2/10/1900
8282 Arthur Cook
8286 William Andrews Enlisted 6/10/1900
I couldn't find any 1915 Casualty listing for Arthur but assumed he was patched up and sent back Overseas but no information if it was 1915 or 1917 when he became MGC -Sorry