You have the ability to be a member and or Administrator of multiple networks at the same time. Once you log into the Regroup interface you can click on your personal avatar in the top right corner of the page.
You then have the opportunity to switch between networks by scrolling down to find the network you would like to manage.
If you would like to change your primary network or leave one of the networks you are assigned to you can simply click "My Profile".
Your individual profile page will appear. To the left you will see a menu selection "Networks" by clicking this selection you will be presented with the networks that you are a member of.
By simply hovering over the network that you are interested in, you can choose to either leave that network or make it your primary network.