I'm not sure I can agree with the statement below. I used to do auditing when I worked for a CPA firm. It's not just about putting together financial statements. That's the easy part, considering it's all computerized these days. You have to actually pull physical documents, such as invoices, billing, contracts, etc., examine and compare them to what has been recorded on the books, as well as seeing if they match the bank statements. Very time consuming and you have to be physically present at the company. Employees of the company need to be available to the auditors to provide any documents that are needed. A pandemic can definitely slow this process down.
Although a company can choose any quarter end as the year end, most companies choose 12/31. This means multiple audit clients right during tax season when they are already working very long hours on taxes. Add to that a pandemic, with employees of the audit clients not being available to provide necessary documents and information, and it is certainly not beyond the realm of possibility that the accounting firm was unable to complete in time.