Can a modification be issue to an expired Delivery Order/Task Order to change the delivery date due to supply lines having issues with the delivery period due to the pandemic?
In a word, yes. You may modify the order to extend the period of performance and accept delivery.
In this instance we will assume you have evaluated all of the facts and agree that the reason for the delay was in fact pandemic related. This is known as an excusable delay. You would have to do a scope determination document for your file and based on the facts conclude that the modification is within the general scope of the contract/order. It was reasonably contemplated at the time of award and it would not have altered the field of original competition. See your legal counsel for support.
How you do it depends on what clause you have on the base contract (or the order, either one). If the base contract and/or order used the commercial contract format (SF 1449) then you have FAR 52.212-4. FAR 52.212-4(f) Excusable Delays identifies “epidemics” and “quarantine restrictions” as excusable delays. The modification authority you would use in block 13.C of the SF 30 would be FAR 52.212-4(c). This would have to be a supplemental agreement (bilateral modification) because of FAR 52.212-4(c).
If you did not use the commercial contract format, look to see if you have FAR 52.249-8. FAR 52.249-8(c) also identifies “epidemics” and “quarantine restrictions” as excusable delays. This clause would not be your modification authority however. You would use “mutual agreement of the parties” in block 13.C of the SF 30 and again utilize a supplemental agreement (bilateral modification). You contract file documentation should cite FAR 43.103(a)(3) as there is no other clause that specifically gives the contracting officer the right to change the period of performance for this situation.