Some time ago we informed that Microsoft doesn't plan any official updates for Windows 10 Mobile in the future. Today Brandon LeBlanc, Senior Program Manager of Windows Insider confirmed that Microsoft's support for Windows 10 Mobile officially ends. In the future Microsoft probably will focus on developing apps for Android system.
However, if you are owner of phone with Windows 10 Mobile system you will still receive some updates for your device. Microsoft will still release monthly security updates for this system, but they won't add new features to it.