Uncertainty and risk are not new or novel to contractors. Contracts reduce uncertainty and share the risk of doing or providing something. COVID-19 may have contributed to, but it has not single-handedly created, uncertainty and risk.
As if you needed confirmation that the Federal Miller Act is a powerful tool for unpaid subcontractors, this is it. Even when a Prime ordered and accepted the Sub’s work, but didn’t have to pay under the Subcontract, the Subcontractor still. . . .
Suppose that you (the Contractor) had extra costs and want payment for those extra costs from the designer.