As far as I can tell, this is the first time a zone has been abbreviated with a ghost letter. As you all know well, the letters can be confused in order, especially UTC, but the letters in time zone abbreviations all represented words, until now.
Also, the time zone now has at least five ways that you can refer to it: 1. Mountain Standard Time. 2. Yukon Standard Time. Yukon got there first, in 2020. (Bonus confusion: Yukon Standard Time used to mean nine hours behind UTC. The Yukon government just redefined it.) 3. Pacific Time. 4. PCT. 5. “Pacific Time (British Columbia).” That’s what Microsoft announced. I found all of this fascinating enough to write a blog post about it, and the possible lesson for the U.S. https://locktheclock.net/time/2026/09/oh-canada-oh-my-dst-lock-the-clock/
