Performance document - Approval restricting when a particular manager submits

Summary:

Want to restrict the performance document approval when one particular manager submits the document of the direct reports

Content (please ensure you mask any confidential information):

Our client wants to restrict the approval process for one particular Line Manager (President) when he / she submits the Year End Performance Document of the direct reports. In this case, this particular line manager will not be have a Line Manager mapped in the system and approval will get stuck, which leads to in completion of year end performance document.

Please suggest a way to have this achieved. We would like to have this achieved via approval configuration.