There is a certain amount of confusion shown in forum and class questions about the difference between Quality Assurance and Quality Control. This video brings some clarity to this topic as well as discussing testing and retesting options.
The User Guide (10.3.2.1, 10.3.2.2) suggests that Owner caused delays (per GC13.1) entitle the Contractor to reimbursement for costs and lost time. In this case, the CA must act impartially and issue a Change Order for the proven impact, even if the CA was the cause of the delay.
The Contract Considerations Video, "Partial vs. Staged Substantial Performance" should provide the answer.
Refer to GC 1..3.8
The Contract Administrator.
Note that the Contract Administrator is the interpreter of the Contract Documents, and the judge both parties to the Contract (GC 3.6.1). Refer to General Conditions regarding Extra Work and Change Orders.
Situation may require legal advice...but check the GCs for sections relevant to the alleged breach.