The initial interview was an open day with another 7/8 people. After an overview of the company and a little bit of insight into the actual job there was an aptitude test covering basic grammar and arithmetic along with a few very basic IT related questions. They allowed us 2 hours to complete it but realistically takes about half an hour to an hour.
A few days later I received an email offering me a formal on site interview. Again there was a small basic aptitude test on a laptop this time, all IT related. Once that was done I had a short 1 on 1 interview. I was offered the job later that same day via a phone call.