[1] It was expected that all the locomotives would be similarly modified, but this did not happen, and the remaining locos were classified as EF1 (Electric Freight 1).

In 1928 a plan was devised to convert one of them to a diesel-electric, using a 1,000 hp Beardmore diesel engine driving an English Electric generator.

[2] Electric traction on the Shildon line was discontinued in 1935 but the locomotives were retained for possible future use.

Number 11 (later BR 26510) was rebuilt in 1941 for use as a banker on the Manchester-Sheffield line, and given the classification EB1 (Electric Banking 1).

In 1949, the plan to convert the remaining nine locomotives as banking engines was dropped and they were reclassified as Class EF1 (Electric Freight 1).