Talking about Ewer Street, serving London Bridge/Cannon Street/Charing Cross, similarly the bigger London termini had their own 'stabling points' for 'turn-round' workings, even Euston had one on the west-side, but was mostly used by outer suburban steam locos like the LMS 2-6-4T's. I can remember seeing exLMS pacifics (from Camden/Willesden) at Broad Street, used on fitted freights from the neighbouring goods depot. 33C, although Shoeburyness was ( and still is) the other end of the Fenchurch Street line, Tilbury's main work was freight from the nearby docks, and a little further away, the oil refineries. Oh, and Bishopsgate became a goods depot not long after the opening of Liverpool Street station, all under the loco operation of Stratford. Phil - for Marylebone you can definitely delete Kentish Town, and add Willesden, but seeing as you ask for 1950, then keep it to just Neasden.