Correct me if I'm wrong but I think as an STG you can get stationed at any ports, but then you know, needs of the Navy I guess. Also I think any rates within the AEF have an option to be advanced to E-4 if you're "graduating at the top of the class". Besides Nukes and SO, free push button E-4 is too good to be true. Also your classifier should have given you a job card about stuff like this.
https://www.cool.navy.mil/usn/enlist...rds/stgaef.pdf
http://www.public.navy.mil/bupers-np...s/1510-030.pdf