Hi mate! that post is from 2015! but ,anyway, rehire process is done by your local agency and they need to send you a rehire documents and you have to provide them with all details of your previous contract and why you signed off ,etc.... then you have to cover your "thing",for example if you said that you broke your arm at home,then you have to prove it...
And after some time,they will (hopefully) accept your rehire and you will be a crew member again
cheers