Interview questions seem fairly standard for most jobs. On my interview I got asked things like:
1. Have you ever been in a position of trust by someone giving you something to look after?
2. Give an example of when you worked as part of a team.
3. Give an example of when you had to work on your own initiative.
4. How would you deal with an customer who is not happy with the service they have received?
5. How do you keep yourself fit?
6. Give an example of when you worked to a deadline.
7. Have you ever done a repetitive job before and what did you do to make it easier?
So you gotta answer this questions before going to your interview with royal mail.