Manager Assessment Editable after submission for approval

Summary

Manager Assessment Editable after submission for approval

Content

The manager is able to edit the performance document even after submitting the performance document for approval. We have a requirement to not allow managers to edit/resubmit, the document after submission. Is there anyway to achieve this? I did find a Doc in MoS which walks through a customization to disable to View button after submission, but that is breaking other parts of the process with buttons being enabled on tasks which shouldn't be.