It's a con/Scam. If you have an interview go do more research into the company and the people that run it. They will "employ" you under a different company and feed you a whole bunch of rubbish which they make out to be very believable but don't waste your time.

The HR who called was very friendly. However, the person who interviewed me was absolutely rude and seemed to have made up his mind that he was to say no. To be frank, it is false advertising and is in fact a marketing job. Where you have to work for hours, only to be paid less. I asked for working hours since the advert said "flexible hours" and the manager interviewing me had a go at me for asking. I live far and therefore had to ask to plan my commute and he just said relocate. Will he pay for that? It was astonishing. He ended the interview saying that asking for working hours means no. I was so glad to finally leave that building. Honestly, why work for a company who seem not to know anything about professionalism and respect. My advice to graduates will be to dodge the bullet.