Very early in my career, I was a tax CPA and my firm's large real estate developer and investor clients had running audits only because their tax returns were so incredibly complex.
Maybe things have changed, but I doubt it.
I’m sure they keep a close eye because of complexity or ‘what ever’ reason - but have a yearly audit ‘just because’ I doubt it. If there wasn’t a problem in previous returns - why the need for an official yearly audit. Now, I’d say all bets are off.