A User that has the Role of 'Driver' has the Home Terminal option set. The available Home Terminal list is populated by the Memberships assigned to the User.
To change a Driver's Home Terminal:
From the Home Terminal list select an Organization (OU)
To add a Home Terminal:
Add a Membership for another OU. The Home Terminal list will now have the option to select the newly added OU.
Note: if the OU you're looking for isn't available in the Membership list of Organizations, you can add a new OU by going to 'Management & Settings' > Organizations.