If you do move up without a ticket upgrade you won't have a seat.
The seats are assigned on tickets but as others have said check with box office no need to get embarrassed being on someone's seat that came late
Yes you can move to the front
You do have the option to upgrade at the event
U can check n see how many tickets r left day of concert. I've seen most start the concert in their seats then move up to empty seats during concert. They are fairly loose with monitoring seats. U can also stop by their window box-office by Amphitheatre n may get a discount price to move up if fairly booked.
Probably, the last concert alot of people did that.
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