When using a connection to Azure Active Directory to create new IP Office users, the connection settings specify which IP Office 'user provisioning rule' to use. That rule:
Sets the starting extension number for new users.
Sets the extension type for the new users using either a specified extension template or specified extension type.
Sets user settings, other than those taken from Azure Active Directory, for the new users using a user template. The IP Office applies default user settings if you do not specify a user template.
Optionally configure on which IP Office in a network the IP Office creates each new user.