You have a customer who currently has a Microsoft 365 subscription and is utilizing the Free edition of Azure Active Directory (Azure AD) for their identity and access management needs. The customer now plans to acquire an Azure subscription and intends to provision multiple Azure resources. To ensure that their security environment is robust and meets best practices, it is essential to evaluate their current setup. Under what circumstances or requirements would it be necessary for the customer to upgrade from the Azure AD Free edition to the Premium edition?