No idea what they might ask non type rated guys but as a general principle, do a bit of research on the company (plenty of info on the website), find out a bit about the nice new shiny thing that will arrive in due course (just go to the Boeing site) and make sure you know your current type, because they probably will.
Friendly and informative but fairly searching was my experience. (I'm type rated).
Any other questions you can ask them on the day, all will be made clear so no point regurgitating it here.
Good luck and hope to meet some of you in due course.
