Suggestions required on how to rollup the Primary Hierarchy in compensation plan based on Number of

Summary

We have a business requirement wherein if any manager has less than 6 direct reports , then the hierarchy should roll one level up

Content

We have a business requirement wherein if any manager has less than 6 direct reports , then the hierarchy should roll one level up and this validation should continue until the a review manager has atleast 6 direct reports.

The eligible direct reports signifies the employees that stand eligible as per the criteria in the compensation plan, for example, the eligibility is based on the list of jobcode, legal employer.

We tried using a fast formula invoking the valueset to get the count and a while loop (until count 6), but the performance has degraded badly.