Seems I may have a different question than the OP even though the words are the same...

The IRS did a 1099 reconcile and "found" credit card "revenue" that was tip pass-through dollars to employees and reported on W2/W3s by ADP, payroll taxes were paid, etc.

The CPAs for prior years all just historically ignored tips on the 1120 since it's not actual revenue; Is this a Line 10/26 thing that wasn't done in error for multiple years or is this an IRS reconciliation anomaly because of an unusual legit Line 10 entry for the year in question?