Termination for default reviews can be done a variety of ways, however, one method is to start with what is the ACTUAL deliverable on the contract, not the one that the customer thought they had. Carefully track what the contractor's actual performance is against the specific language in the contract. If there has been verbal changes by the Government without going through the contracting officer (which should never happen), is there something that indicates the contractor consented to those changes? In writing? For example, the DFARS 252.212-4 clause section that deals with modifications states that mutual consent is required for all modifications. In this review, use the language from the contract and then see if you have adequate evidence from the Government documenting the actual performance. Ask if the Government COR has signed any receiving reports e.g., DD Form 250s accepting performance (so they can get paid). Is there anything in the record that shows the Government placed the contractor on notice of their default or non conforming deliveries?