 Following Grouping, ownership and management of the line was taken over by an MSJ&AR Committee, representing both the London, Midland and Scottish Railway (LMS) and the London and North Eastern Railway (LNER).The LNER was particularly interested in the electrification of mainline railways and in 1928 a government report had recommended 1500 V DC overhead as the national standard system.Despite the LNER's enthusiasm for electric traction, the LMS was the company responsible for installing most of the new electrification infrastructure on the line, while 22 new 3-car electric multiple units (EMUs) were built for the line by Metropolitan-Cammell to an LMS design.