eGO is a single organization - once you're in for one division, you're in for all.
You may:
- Change your division tag (the one under your e) at any time through your user profile.
- Play on any eGO server with your tags on
- If you have admin (eG or eGO) for one Source game (tf2/dods/css/ins) you automatically have admin in all. For COD games, you will need to talk to one of the COD DL's. They have to add you to a different system, but there's no other requirements as far as I know (for questions regarding their system, contact their leadership)
There is no need to contact leadership or go through any process to 'switch' divisions. Feel free to play wherever!