If you're going for an assistant job, and the first interview is with just band/fine arts folks, and then round 2 is with principals...that's a good sign that admin trusts their team.

For head jobs, if the principal knows the ins and outs of the program (how many kids are in band, what the schedule is, past ratings)...that's a good sign. If they toss those answers to the assistant director or someone else in the room...that could be a red flag. If there is an assistant, and they're not in the room, maybe ask, cuz that's either a sign that they are leaving, or the admin is trash.