You should go thru your CoC in the official sense. You might have a contact at the unit you want to transfer to who is saying yes you can go there, but that isn't official.
The G1 folks at your Bde HQ will need to be involved, which means your Unit CoC will need to initiate the paperwork for the transfer, etc. If you are going from one CBG to another CBG in the same Area, that involves more. If you are transferring Areas...well you get the point I think.
Engage your CoC now, so they have time to staff the paperwork. With the cutbacks in Class A and B wages, waiting might ensure this doesn't happen for you.
:2c: