Bad service

My insurance company referred me to Automagic which sub-contracted Interstate Bodyworks for repairs, my car went in for repairs on 28/09/2015 and I was told it would be ready for completion on 09/10/2015 , After receiving no updates from the repairer, I called them on the 9th in the morning to check if my car was ready for collection, I was told it still needs to be polished and painted. The date for collection was moved to the 13th. I called again on 12/10/2015 to check the status of my car, I was told they have a backlog and it should be ready on the 14/10/2015. I have called Automagic as well to do a proper follow up on the car, but they told me there is nothing they can do on their side. This is such an inconvenience, if Interstate Bodyworks was overloaded with work, then they should not have agreed to do the repairs! I haven't received any updates today that the car will be ready for collection tomorrow.