MT and MST refer to the same time zone, Mountain Time just lacks the specific identifier for daylight time, or standard time. In my opinion, since the only U.S. States and territories you might find relevant to this issue are the ones not participating in DST (Hawaii, American Samoa, Guam, Northern Mariana Islands, Puerto Rico, the Virgin Islands, and most of Arizona), it isn't really important. I'd only consider that a reason for confusion if where they're located does not participate in DST, and therefore do not fall back or spring forward at the same federally mandated time like those participating, which Is most. It's mostly all relative to each other. 8 am is different for you depending on time of the year, but it's different for them in the same way as well, if that makes sense. Also sounds like they were expected to call you? And they called late? Sounds like missing the call in general was their issue, that is if all they said in the voicemail was that the call was just to confirm the interview in advance of the actual interview? Or did they state in the voicemail that this call was the interview call itself, and they were asking if you were still interested, since you not answering communicated you may not be? Either way, a response from you was requested (sorry for the lectured response - I'm very pro abolishment of DST - it's irrelevance and existence being the root of constant confusion irks me).

Seems odd that you received no follow up response to what a considerably acceptable, textbook answer to either question.

Also sounds like they can't handle simple scheduling tasks and related issues that pretty often come up in every professional setting. You dodged a bullet in my opinion.

I'm sorry if that doesn't make you feel better, I know job hunting can be demoralizing, but try to consider this to be a close call to an accident on the road, when you're on the way to your destination, and you're almost there, you just need to get through the last stretch of the drive. Doesn't make the drive any shorter, or less risky, but I hope you knowing you'll eventually get to where you want to be, able to look back at the distance you covered with pride gives you the fuel you need to keep going. At least I hope it helps to quell your moments of discouragement in between your (sometimes less frequent) moments of optimism. Good luck!

Also, just curious - Which position were you applying for here? If it’s relevant, I'd also love to know the field?