When a contractor is challenging the assessment of liquidated damages, or arguing that it is entitled to extended general conditions, the contractor bears a burden of proof to establish there were excusable delays that impacted the critical path and, in certain scenarios, the delays were not concurrent with contractor-caused delay:

When delays are excusable, a contractor is entitled to a time extension, such that the government may not assess liquidated damages for those delays. The government bears the initial burden of proving that the contractor failed to meet the contract completion date, and that the period of time for which the government assessed liquidated damages was correct. If the government makes such a showing, the burden shifts to the contractor to show that its failure to timely complete the work was excusable. To show an excusable delay, a contractor must show that the delay resulted from “unforeseeable causes beyond the control and without the fault or negligence of the Contractor.” “In addition, the unforeseeable cause must delay the overall contract completion; i.e., it must affect the critical path of performance.” Further, the contractor must show that there was no concurrent delay.

Ken Laster Co., ASBCA No. 61292, 2020 WL 5270322 (ASBCA 2020) (internal citations omitted).