- Upload applications through the Azure portal
- Get early access to Windows Updates on secure virtual machines
- Test applications in various configurations and environments
- Collect feedback on application performance, functionality, and stability Microsoft has recently announced that Test Base for Microsoft 365 will be deprecated, meaning that it will be discontinued in the future and no longer available for use. The exact date of retirement has not been confirmed yet by Microsoft.

(https://learn.microsoft.com/en-us/windows/whats-new/deprecated-features)