Reporting is available for plans as well as premium plans (project). Data is stored in separate locations, so the approach for reporting will depend on what kinds of plans you're looking to build reports on.

• Premium plans (projects) are stored in Dataverse. If you're using Power BI, you can use the Dataverse connector to build reports on data in your environment. The free Power BI template can help you quickly get started.
• Basic plans are stored in Azure. You can query the data using our public Graph API. https://learn.microsoft.com/en-us/graph/api/resources/planner-overview?view=graph-rest-beta