I was often on the station from about 1959 onwards and have no recollection of a subway between platforms 1,2/3,4. I recently was looking at some old photos from early 1950s and they definitely show staircase entry to a subway and signs directing to other platforms. The question is why? There was an wide access bridge alongside Guide Lane which served all platforms and a goods lift down to each, destroyed by fire in this century. Most of the station was re-built around 1904 with the 4 tracking scheme between Ardwick and Hyde Junction so the subway and bridge would date from then. Just seems like an unnecessary extravagance .