Actually, it's an arbitrator, not a mediator. And the question he's being asked to rule on is whether the "PBS Process Agreement" which was published in the failed TA is still in force or not. If not, the XJT MEC must negotiate with the ASA MEC to create a new one before they can continue with SmartPref. If he rules it is still in effect, nothing changes.

The arbitrator is NOT ruling on which PBS system to use, and really not settling anything. The suit by the ASA MEC is to try and stop the XJT MEC from doing an end run around them in negotiations for lesser work rules that will eventually affect all of us.