Hi m1234,
Well done on getting an interview. I had mine for Sheffield back in May, which I was successful at but got put into the talent pool, which worried me a little but I've since been given a start date so I'm really happy about that.
The interview I had was I suppose, exactly as you'd imagine.
A few situational scenarios such as what would you do if ... (Dealing with a disabled person needing assistance in my case)
Tell us about a situation when ( you feel you provided excellent customer service in my case)
Tell us about dealing with a stressful situation (we'd just moved house so I went through that with them)
What you do you do to unwind?
How would you get to work assuming there's no available parking and you're working one of the first services so no option to use the train (I ride a motorcycle so no issues).
Then a general chat.
They were really nice blokes, and absolutely put me at ease. Even so, I didn't think I'd done that well...
Hope your interview goes well.