I had accepted an offer for a contract role, the contract was drawn up, signed by the Agency and my Umbrella company on my behalf on a Friday with assignment commencement being the following Monday. At this stage the agency commenced basic vetting which they completed, satisfactorily, on the Monday. However, on the Friday evening I received a call from the Agency not to go to the site on the Monday as the client had now requested Level 3 vetting to be performed. I received an enhanced questionnaire on the Monday which I completed. But this uncovered something that caused the client concern (which was not related to anything criminal or financial circumstances) and, on the Wednesday, I was told by the agency that the offer had been withdrawn. The contract had a 5-day notice period written in but the Agency said this didn't apply as the assignment had not started. So the client actually changed the requirement after the contract had been signed. What are my rights in respect of compensation for the 3 days lost?