I admit trouble on this myself.

So the system time as shown in game lists itself as MT. But whenever I set stuff for MT it only ends up matching the server sometimes. Which I assume has to do with time savings stuff - I've tried a lot of times to match, and so instead of ####ing around with the server time being pseudo-MT, I just pick what matches it.

It just so happens it currently matches Central Time, so I use CT on the calendar and what not to schedule things.

As to the specifics of the questions - I have no idea and it regularly frustrates me too. That's why when I post most events, or when I edit times listed on others' events, I always include a "X EST" followup to make sure we're all clear on when it is. Since I, at least, know EST.

-Ish