I'll tell you that among a lot of Canadians who are multilingual, but not including knowledge of both official languages, there's a strong feeling—not a feeling, it's a fact if you ask me—that they are shut out of federal government employment.
In your strategy to take care of the directors or senior auditors, I am speculating that if two chartered accountants apply and one is bilingual and the other is unilingual, my guess is that you'll automatically recruit the bilingual person.