Meet and Greet - Advice?

I won a meet-and-greet with UM this Friday the 2nd. It was a Head Count contest.
I’ve never done anything like this. Any advice?

What’s a pre-show meeting like this typically involve? Photo op? I chill while they warm up backstage? Do we legit talk for a certain amount of time? Is the whole band typically there, or only some?

What would you ask if you had this chance?