Mis-filed as COPPINS in the WW1 Service Records (WO 363):

John Charles COPPIN, born about 1888, married Bertha Ethel BAKER 1912, son John Cecil Edward born 1913. Enlisted 1916 - trade "Music Hall Artist".
Which made me curious, and Mr Google led me to Charles Coppin & Bertha Baker, "Haig & Esco", parents of Jack Haig, actor, born 1913. "It is I, Leclerc!"

Anc****y, COP, pages 13699 to 13720