How does the performance process work for employee when primary assignment is changed?

Summary:

Scenario:

Employee has 1 primary assignment. Performance eligibility was processed and document was created.

While the document is still open, employee has a new assignment which becomes his primary assignment. So employee now actually loses eligibility to the previously assigned perf doc.

What happens in this scenario?

1. When the elig process and perf doc creation process runs the next time, will it create a new document for the employee for the new primary assignment
2. If yes, what happens to the old doc created with the original primary assignment ? Will both be available to the employee in the employees performance page ?