DWP telephone call versus consultation - advance notice of questions

Hi I applied for Pip. Got first DWP phone call yesterday asked if it was convenient to speak I said no arranged to speak this morning. I thought it would be a phone call to arrange an appointment. It wasn't it was a phone call to run through my PIP application instead of having a consultation. I said fine but I would like to have someone with me so the nurse said, if i would rather have a consultation that was fine and could be booked. I said what's the difference she said the brief (30mins!) discussion on the phone with her to help her decide on some descriptors is to avoid a consultation. I said I'm happy to do that but I would like someone with me. I am now doing the phone call tomorrow with my sister. The nurse gave me quite detailed information on about 10 points that she wants to discuss with me. For example washing and dressing affect on upper body what's the pain like how long to complete do I rest after. Even though this is all on the phone.
Questions:
1 is this phone call opposed to a consultation normal?
2 is it normal to be given advance warning regarding the questions I'll be asked or is that a trick?