By 1908 it was obsolete and replaced in British Regular Army brigades by the modern QF 4.5-inch howitzer.

Territorial Force brigades, however, continued to use the howitzer in World War I into 1916, including notably in the East African campaign.

A lighter 40-pound (18.14 kg) shell with Amatol filling replaced the original 50-pound (22.68 kg)  Lyddite shell early in World War I Together with an increase in cordite propellant from 11 oz 7 drams to 14 oz 5 drams, this increased the maximum range from 4,800 to 6,500 yards (5,900 m).
Administrative error led to the new 40-pound shells being sent to Gallipoli without range tables or fuze keys for the new pattern fuzes, rendering them useless.
By 1908 it was obsolete and replaced in British Regular Army brigades by the modern QF 4.5-inch howitzer.
Territorial Force brigades, however, continued to use the howitzer in World War I into 1916, including notably in the East African campaign.
A lighter 40-pound (18.14 kg) shell with Amatol filling replaced the original 50-pound (22.68 kg)  Lyddite shell early in World War I Together with an increase in cordite propellant from 11 oz 7 drams to 14 oz 5 drams, this increased the maximum range from 4,800 to 6,500 yards (5,900 m). Administrative error led to the new 40-pound shells being sent to Gallipoli without range tables or fuze keys for the new pattern fuzes, rendering them useless.
BL 5-inch howitzer