Hi @c.willard
I just checked in my new Teams, but the setting to change time format within Teams is not currently available.
However, while we await when it will be available you can revert back to the classic Teams to be able to change the time format in Teams. If you'd like to switch back to classic Teams, it's easy to toggle back and forth. To switch back to the classic Teams, turn off the New Teams toggle at the top of Teams.
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