interviewing with current employer
 

I have an interview for a supervisor position at the company I've been with for 4 years. The interviews will last all day and will be with people that already know me and my professional work very well. Do you have any tips specific to this type of interview?

Most of the interview advice I see is for interviewing with a new company that is unfamiliar with you.

Interview is interview whether they know you or don't. I just can't comprehend why does it have to be all day.... Don't they know you already or are you applying for a position in different department? Are there going to be other people interviewed for the same position?