Time Standards for Closeout of Order Under GSA FSS by Office Admin Contract

Scenario: A CO/KO issues two separate FFP delivery orders for supplies to be delivered within 30-days from time of award. One delivery order is awarded for $100k. The other is $160k. Contractor delivers supplies within 30-day timeframe. Supplies are inspected, and accepted by Government. Contractor submits two invoices 30-days after Government accepts supplies, one for $100k, the other for $160k. Government renders payment within allowable timeframe for full amount of each invoice.

Question: Does the office administering the contract, ordering agency in this case, follow the time standards in FAR 4.804-1 for closing out the two FFP orders issued against the vendors GSA FSS Contract? If so, what time standard is applicable (i.e. [a][1], [a][2], [a][3], [a][4], or neither)? If neither, what time standard would be applicable, and why?

My Thought: Follow time standards in Federal Acquisition Regulation 4.804-1[a][2]:

Files for firm-fixed-price contracts, other than those using simplified acquisition procedures, should be closed within 6 months after the date on which the contracting officer receives evidence of physical completion.

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