The performance appraisal has two deadlines associated with it:
- Manager's evaluation
Once the self-review deadline is reached, the employee will still be able to submit his/her responses but will not be able to modify them afterwards.
Once the manager deadline is reached, the manager will no longer be able to modify his/her responses that were previously submitted.
The manager will still be able to submit his/her responses after the "Manager deadline" has been reached, but he/she will not be able to make any modifications.
The manager will also be able to share the results after the deadline is reached.
In summary, after the deadline is reached, the manager will not get any more reminders about that task and they will not be able to make modifications to the appraisal itself.
If you want to allow either the employee or manager to modify (or submit) his/her responses on an appraisal that has reached its deadline, you'll need to modify the deadline.
For more information about ways to extend deadlines of performance appraisals please refer to this document.