From 15 September 1958 all Altrincham trains were cut back to the bay platform at Oxford Road to allow the reconstruction to proceed at London Road. The short section between Piccadilly and Oxford Road stations was converted to 25 kV AC, and on 21 September 1960, suburban electric services from the Styal and Stockport lines began to use Oxford Road as their city terminus. By the late 1960s the Altrincham Electrics were approaching forty years of age. Rather than replace them with new rolling stock operating on the non-standard 1500 V DC system, the decision was made to withdraw the trains and convert the whole Altrincham line to 25 kV AC. The last 1500 V DC train was the 23:35 from Oxford Road on 30 April 1971. Altrincham depot closed and all the 1931 rolling stock (provisionally assigned to Class 505 by British Rail) was withdrawn from service. On Monday 3 May 1971, a 15-minute interval service was introduced from Altrincham, running through Manchester Piccadilly to Alderley Edge and Crewe. The unique 40-year-old, three-car Altrincham Electrics were replaced by 12-year-old, four-car Class 304 25 kV AC EMUs, based at Longsight depot. Three of the 1931 stock centre trailer cars were preserved and two are now undergoing restoration at the Midland Railway - Butterley in Derbyshire. However none of the motor coaches was preserved. Following conversion in 1971, the AC services on the Altrincham line continued relatively unchanged for the next twenty years. The Manchester Metrolink is a light rail scheme introduced in the Manchester area in the early 1990s with the aims of reducing traffic congestion by providing modern, attractive public transport options for journeys into the city centre, and offering more convenient interchange between the rail systems north and south of the city. Phase I of Metrolink involved converting the British Rail lines from Victoria to Bury and Piccadilly to Altrincham to light rail operation, and linking the two by a street-running section through the city centre. The conversion of the Altrincham line to Metrolink was originally stated to require no more than six weeks. In the event, the line was closed for some six months, during which time both all-stations and a rush-hour express (first stop Sale) substitute bus services were provided. Rail tickets were valid on the replacement buses, operated by the North Western Road Car Company and running daily except Sundays.