Can the performance rating entered in Manager evaluation task be altered in Manager Final Feedback?

Summary:

We are setting up performance improvement plan in TEST. Following is the required process flow

Manager Evaluation -- Where Manager fills a questionnaire of objectives
Employee Evaluation -- Where employee fills a questionnaire of action plan
Employee Feedback -- At the end of the performance year
Manager Feedback -- At the end of the performance year, manager enters the final feedback along with rating

As overall summary section along with rating can be associated only with Manager evaluations, we are looking for a way for Manager to enter the rating while doing the final feedback.

I didn't checked the option in Process flow "Don't allow additional edit of manager evaluation task when completed" and expecting the rating can be updated by manager later in process flow at Manager Feedback stage. But the rating is not updatable in Manager Feedback stage by manager.