evoterra, 
One of my biggest pet peeves is people using MST as a time zone when Daylight Savings Time (MDT) is in effect.
STOP PUTTING IN “S” OR “D” unless you have a very good reason to do so—and you very likely do not!
I just showed up for a 6p MST meeting at 6p MST (it’s always MST in AZ) and was an hour late because the hosts meant 6:00 MDT, which is 5:00 MST.
Had it simply read “6p MT” I’d have been on time. 🤬
/rant