Global Temporary Assignment

Hello experts -

I want to know whats the general practice used which initiating Global Temporary Assignment.

1) There is a field in When and Why called " When do you expect the new work relationship to end?" used to track end date. But this date is not accessible anywhere. Is the end date of temp assignment tracked on this date or Projected End Date.

2) If I need to extend an Assignment, do I need to update Projected End date with a new date?

3) I am unable to see "End Global Temporary Assignment" in Change Assignment if I have end the assignment early. What could be the reason for this? I checked in Configure Actions, this action is active and able to see in the classic pages but not in responsive pages.