It will be interesting to see what the OSG does with this. The last time a circuit split developed in similar circumstances, the government brought a cert petition and essentially concurred with the tribal cert petition (Cherokee Nation v. Leavitt).
Here are the materials:
Here is the question presented:
Whether the Federal Circuit erred in holding, in direct conflict with the Tenth Circuit, that a government contractor which has fully performed its end of the bargain has no remedy when a government agency overcommits itself to other projects and, as a result, does not have enough money left in its annual appropriation to pay the contractor.
Here are the lower court materials.
And here are the materials in Ramah, the Tenth Circuit case that generates the circuit split.