I kind of go along with what Rich66 is saying too !
I don't know which airline has called you for interview, but, in other industries, e.g. engineering, if you start getting messed around at interview stage you have to ask 'Do I really want to work for these people ?'. Same to be said about the interviewer. I've met one or two and thought, 'Do I really want to work for this tosser?'
Anecdotally, in some of these instances, I've known other people who either got the job, took the job, or went to work for XYZ later on. They all told me what Mr.X or company XYZ were live to work for and confirmed my suspicions ! Toss !!
CG