A third batch of fifty locomotives were later built by North British Locomotive Company in 1949-1950 as part of Operation Phoenix, the postwar rebuilding of Victorian Railways. A fourth batch of twenty N class of a modified design were also ordered from Newport Workshops. The class at this time was renumbered, with numbers 400-429 assigned to the pre-war Newport locomotives, 450-499 assigned to the North British locomotives, and 430-449 reserved for the postwar Newport locomotives. However, production of the fourth batch ceased in 1951 after just three had been built, as VR opted to order more of a new design of 2-8-0 branch line locomotive, the J class. VR also decided to sell ten of the North British-built N class locomotives (N's 461, 465, 471, 474, 477, 485, 490, 491, 494, and 495) to South Australian Railways, which was experiencing a motive power shortage, where they became that system's 750 class. Many of these locomotives had only run a few days in VR service before being transferred to the SAR.