Update, had a call today from the director asking me to go back on Monday. He apologised about the lack of organisation on their part and the hurried way in which I was sent home. I explained that I just wasn't sure what to think of the situation but he assures me there is no problem and it was simply a workflow panic and that perhaps they did the wrong thing. So, back to it Monday, working for a different department but should be in my old seat and it should keep me busy for 2 months until the main project takes off proper.