With regard to upgrading and the ban I think that the ban effects new hires only. To be in a position to take an upgrade then take it.
The ban is a hiring ban not an upgrade ban as I recall. Take the upgrade and the company will soon be needing SO's, FO's.
Oh by the way - hope progress is made soon on the ban front, it's a tough situation to be in and I for one wouldn't want to confront it but maybe I will in the future. Anyway hope it works out for all parties concerned and please start the hiring again soon.