Complex sentence: Staffing by this point had increased to two porters and two lad porters, managed by the stationmaster at, but by 1961 was reduced to two porters, then one in 1965.
Split into simpler sentences: Staffing by this point had increased to two porters and two lad porters, managed by the stationmaster at. By 1961 this was reduced to two porters, then to one in 1965.