Changing Absence Approver if a Project Manager is Assigned/ not Assigned

Hi Experts,

Hoping we could get some help regarding a design problem we are trying to solve regarding Absence Approval routing.

The design we are trying to implement incorporates changing manager hierarchy based on whether a worker is assigned to a project.

Once assigned to a project, they will be assigned a project manager. In which case, their absence approval (specific to 3 absence types) should route to the project manager and HR Representative at the same time.

Otherwise, if they are not assigned to a project, their absence approval should route to their line manager and HR Representative at the same time.