The rates in the contract wouldnt be used for long anyway. It would take a while for them to order the planes and get them on property. By the time all of that fell into place we'd be coming up on contract negotiations. So arguing about the payrates that are on the books now is pretty pointless. Get them on property and we can get better rates for them.
Also we dont have rates for the C-Series in the contract so that would have to be negotiated after they were ordered anyway.