As a reminder, the USA's mainland (aka the lower 48) spans 4 time zones. There are additional zones for the territories and the portion that is not contiguous. Through, in US usage (unless that's changed), means the end of the day on that date. That said, the abbreviation '-' could mean to or through. So, it is best that they settle on one usage, currently that is 'through'.
Server reset time is Midnight Pacific Time (US), which is UTC -8 when not on Daylight Savings Time and UTC -7 when on Daylight Savings Time, aka 3AM Eastern Time (US). There is also, I think, a holdover from the old days. USA television was broadcast on Eastern Time for most of the continental USA and on Pacific Time for the western parts, so the nightly news advertisements were 9 PM Eastern/Pacific. Since I've never lived in the Mountain time zone and only briefly visited there, I don't know if they got their feed from the Eastern TV broadcast or the Western one. Likewise for the AK/HI zone, which is two hours behind Pacific Time. These days, though, I suspect it doesn't matter much.
"No sadder words of tongue or pen are the words: 'Might have been'." -- John Greenleaf Whittier
"Do or do not. There is no try." -- Yoda
On planet Earth, there is a try.
Indeed, in a world and life full of change, the only constant is human nature (A is A, after all :P).
We old vets need to keep in mind those who come after us.