Graphite admins manage users and billing information for their organization.
If you have admin or owner privileges in Github, you are automatically an admin for that organization in Graphite.
If you enter payment details in Graphite, you become a Graphite admin for that organization.
Being a Graphite admin does not grant you additional privileges in GitHub.
Graphite admins can invite users in Settings > Members in the Graphite app.
A Graphite admin can make anyone in their organization a Graphite admin (even if they're not an owner in GitHub).
Graphite admins can change Graphite admins (who aren't GitHub owners) to "member" status. This means GitHub owners are always Graphite admins (and this is immutable).
Only admins can:
Pay through the billing portal
View active members