I've been through several audits in my career, it isn't merely just an accounting audit to make sure numbers add up, they crawl up your work processes and make sure there is separation of duties as well. This is part of GAAP compliance. For example, they make sure that people who have the authority to write checks, aren't able to write one for themselves, etc.
This is going to be tricky since for quite some time Ed was a one-man show. They just have to make an attestation that Ed knowingly never did anything unethical, and if there were any "oopsies" then they make sure the Ed understands the new process he needs to follow.
I think best case scenario, all years will be completed by end of this calendar year. Worse case, by Q4.