I was asked to apply for a casual position with a large organisation. I did apply and was successful in gaining employment. I was given a 3 month contract with a clear end date of 11 Nov. Today 6 weeks into the position i was informed at 11am this morning that my position was only made available to cover a maternity leave position. The employee on maternity leave has now resigned so my position will therefore end immediately and I was asked to leave the building within 30 minutes. Unfair work relations ombudsman web page says you must be employed for at least 6mths before its considered unfair dismissal. I was assured my conduct was not in question but I had to leave anyway. Does a contract not count as binding agreement in this case?