LJ - agreed; we'd already narrowed the image to 1957 or 1958, My feeling (mainly due to the apparent F/O rank, but also because the 5-bar rail is hugely reminiscent of the Empress of France's upper promenade/lifeboat deck - admittedly a long shot!) is the return journey in 1958; but I don't think it's Liverpool - the Empress of France would have probably discharged passengers at Princess landing stage, then berthed at the Canadian Pacific quay in Gladstone Dock; it doesn't look like contemporary images of either. Similarly, the skyline doesn't remind me of Montreal. So rather at a loss for the location. She also may possibly have stopped off at Quebec, or bunkered at Halifax, before the Atlantic crossing? C'mon, Ppruners with transatlantic crossing experience!
ExA2 - disagreed; whilst the Tudor crown was named after the Tudor dynasty, the St Edward's Crown was named after Edward the Confessor, canonised in 1161.
To return to the subject in hand; one more London Gazette entry for you, Chris - transfer to the reserve noted on 8th Nov 1958 (recorded in the 28th Nov Supplement). This corroborates with the seniority of promotion to Flying Officer in the reserve, at your post #25; but also signifies the date that the National Service period ended.