From my experience, they open right at the start time of whatever movie plays first that day, and most times there is no one in the box, only computers that you pay at.
You can purchase online much easier
Do not know, cannot get to the movies that early
As long as the theater is open. Seen it open as early as 10am
The box office is rarely open save for big releases. You can purchase online or at the concession stand :-)
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