https://www.cnet.com/news/microsoft-advises-users-switch-to-android-ios-as-it-ends-windows-10-mobile-support/

Windows 10 Mobile version 1709, released in October 2017, is the platform's final release. Users won't be able to get security updates after Dec. 10. Support will end on that date for all Windows 10 Mobile products, including Windows 10 Mobile and Windows 10 Mobile Enterprise, the company wrote in another FAQ.

The move may not come as much of a surprise. Joe Belfiore, corporate vice president of Windows 10, tweeted in October 2017 that Microsoft would continue to support Windows 10 Mobile with bug fixes and security updates, but new features and hardware would no longer be the focus.