Their time on earth has expired. They are wanted back on their home planets and a mother ship has been dispatched to beam them up. If they stay beyond their assigned times our atmosphere will absorb them and they will turn into nothing. Not to different from what they are now but hey, either way their departure will create a vacuum.
Just my theory !!!
There is a great deal of speculation and trepidation on where this Department is going now, what direction it will take. Regardless what happens this Association will always be there to ensure that the best interests of our members are always protected.