The contractor issue all hinges on this one grievance picked to lead the rest how this one gets decieded they all do.
The company is betting that they can offer enough money to those people affected by that grievance (in Dallas) that they will take the money and in return withdraw the grievance and the company will agree to put all road drivers back to work.
In other words if the guys in Dallas agree to withdraw the grievance the company will agree to not use contractors while roaddrivers are laidoff, if the guys in Dallas agree to that then they will get there "backpay" no one else will backpay.