As well as adding to the already-confusing mess of timezones and date calculations, daylight savings can change frequently, and sometimes at very short notice.

As well as adding to the already-confusing mess of timezones and date calculations, daylight savings can change frequently, and sometimes at very short notice. This year, Azerbaijan decided to cancel DST, and agreed the cancellation just 10 days before the scheduled clock change [1]. Egypt cancelled DST with even less notice - just 3 days! [2] [1] http://www.timeanddate.com/news/time/no-dst-azerbaijan.html http://www.timeanddate.com/news/time/no-dst-azerbaijan.html [2] https://www.washingtonpost.com/news/worldviews/wp/2016/07/06/egypt-cancelled-daylight-savings-time-three-days-before-it-was-due-to-start/ https://www.washingtonpost.com/news/worldviews/wp/2016/07/06...