Here is a summary and the main article about Test Base for Microsoft 365 from BetaNews: Microsoft to End Test Base for Microsoft 365
Microsoft has announced the end-of-life (EOL) for its "Test Base for Microsoft 365" cloud service. The EOL transition started at the beginning of March and will be finished by the end of May.
Test Base for Microsoft 365 was a cloud-based app testing service hosted on Azure. It allowed organizations to test the compatibility of their applications with new versions and updates of Windows before deploying them.
Microsoft’s main reason for shutting the service is the improvements in Windows 11. The company claims that, due to continuous innovation in Windows 11, compatibility issues with apps are now rare, making the dedicated service less necessary.
The announcement clarifies that most software vendors and enterprises can now be more confident that their apps will run smoothly after Windows updates without the need for extensive external testing.