FAR 43.102(a) says only contracting officers acting within the scope of their authority are empowered to execute contract modifications on behalf of the Government. Other Government personnel shall not execute modifications, act so as to cause the contractor to believe they have authority to bind the Government, or direct or encourage the contractor to perform work that should be the subject of a contract modification. FAR 1.602-2(d)(5) states that a contracting officer’s representative has no authority to make commitments or changes that affect price, quality, quantity, delivery, or other terms and conditions, or to direct the contractor to operate in conflict with the contract.
FAR 43.103 splits modifications into bilateral supplemental agreements, signed by the contractor and the contracting officer, and unilateral modifications signed only by the contracting officer, such as administrative changes, change orders, certain clause-authorized changes, and termination notices. If FAR 52.212-4 is in a commercial contract, paragraph (c) says changes in the terms and conditions may be made only by written agreement of the parties. A COR email that says “add twelve posts this week” is not that agreement.
AsherGate does not route a modification, calculate an equitable adjustment, or tell you a COR email is authorized. Store the written modification PDF after the contracting officer issues it. Until then, perform the current award. Do not ship extra quantity because someone asked in email.