Your email address (and password) are the way that you logon to the GVO.
The GVO allows the same email address (and password) to be used in more than one GVO (multiple GVOs). This can be very handy if you are a clerk or governor at more than one school/college.
The user profile you have in each GVO can be different (eg you can be an Editor in one GVO and an Author in another).
When you sign in to the GVO (if you have an account in more than one GVO) you will see the list of GVOs where you have an account - select the one you wish to go to.
2. If you have finished your work in one GVO and wish to switch to another then select your username (top right) and press 'Select GVO'
You will be taken to the GVO you have selected (and your user profile will be the one for that school)