It operated as a bomber squadron in the 1920s and 1930s, but was disbanded before the outbreak of the Second World War.

503 (Bombing) Squadron of the Special Reserve,[2] manned by part-time volunteers.

Some squadron members thought the Hyderabad superior to the Hinaidi, but when a squadron member discovered dry rot in the longeron of a Hyderabad they settled for the 'newcomer', some almost having spent their life of 700 flying hours already.

[3] In October 1935, it changed role again to become a day bomber squadron, receiving Westland Wallaces.

However, in 1938 it was decided to switch the role of the Auxiliary Air Force to that of air defence, and on 1 November 503 Squadron was disbanded by renumbering it to No.616 (South Yorkshire) Squadron and moving it to RAF Doncaster.