Performance Appraisal - EE leaves the company - How to handle document?

Hello

We are implementing Performance Appraisal and need assistance with a few fundamental questions:

Q.1 If an appraisal form has been started for an employee and employee leaves the company, what should be done with the form as a best business practice? How is it best achieved?

Q.2 If an employee changes managers during the year all managers must be included in the appraisal process. Can this be done automatically? If so, should they be part appraisers?

Please advice. Many thanks in advance.