Well, it seems that I was misinformed. The switch from daylight saving here in Australia takes place next Sunday, 5 April. In the circumstances, my comment about the maritime world using UTC (Coordinated Universal Time) was apt.
When on a long voyage, it’s up to the skipper to decide when the ship’s clock should be changed to reflect the crossing of the meridians, including the International Date Line. Such changes, of course, would affect the timing of the changes of watch – and I mean when the crew go on and come off watch, not what you have on your wrist! The skipper and/or navigator also has to keep track of times of skeds and weather forecasts to keep in touch with the world and get informed about the weather conditions coming their way.