[sdm]

> There are actually two timezones that are canonically named "CST", and they're 14 hours apart!

Yup. If you say CST do you mean China Standard Time or Central Standard Time? The answer will depend on where you live in the world. There are others that share the same abbreviation as well. But CST is the one that constantly causes trouble in daily life. Just say no.

[soco]

According to Wikipedia there are more than one overlappings: https://en.wikipedia.org/wiki/List_of_time_zone_abbreviation...

[messe]

I think BST, CST and IST are the only triple overlaps. I live in one and I'm adjacent to another.

[messe]

As a support engineer living in Dublin “IST” is the bane of my life.

[javbit]

I got bit by this when scheduling an interview. It's interesting because it's not that much harder to say America/Chicago (or just Chicago) but it's just by default I tend to say CST, CDT, etc. Started using UTC offsets but not many people know those off the top of their heads.

[ycombobreaker]

I find using the Olson DB names works in real life too--everybody understands "9AM Chicago" vs. "9AM Shanghai". Major international city names have fewer hash collisions than TZ abbreviations.