Students’ Union UCL interview questions

I received an email inviting me to book an interview up to 20 minutes, but then the actual calendar invite was only 10 minutes long. It ended up being approximately 30 minutes long. There was no indication of what the interview will entail and as the calendar event was only 10 minutes long, I wasn't sure what I needed to prepare for. It was then a full blown interview with four solid interview questions.