How to Skip an Approval Level based on Management Hierarchy of Employee Assignment

Summary:

We have an approval requirement where the Project Manager(s) need to be the first level of approval, then the Line Manager, then the HR Representative. Employees can have up to 3 project managers assigned at one time for each project they are assigned.

In attempts to meet this, we have built 3 levels of project managers in the Supervisor Type Lookup (PM1, PM2, PM3). Then, within the approval rules, the first level of approval is the Project Manager 1, then PM2, PM3, Line Manager, and finally HR (Illustrated below).

The issue we are trying to solve is: what if an employee is only assigned