Microsoft has already released latest Windows 10 Mobile build 10586.164 for slow ring insiders and release preview ring insiders and has also pushed the build as March OS update to non-insiders with a device shipped with Windows 10 Mobile. Alcatel OneTouch Fierce XL on T-Mobile is now receiving  same update that takes the OS version to 10.0.10586.164 .

Change log :

  • Improvements for the reliability of app notifications, including text messages and alarms not ringing as scheduled.
  • Improvements for text message backup to reduce data and battery usage.
  • Fixes for Microsoft Edge with address bar suggestions showing late or persisting during navigation, “Close all tabs” not closing all tabs, and Word Flow on the address bar not functioning as expected.
  • Fix for a problem where the Microsoft account was not detected by the Outlook Mail, Outlook Calendar and People app. Attempting to add a new contact in this state caused the People app to crash for some users.
  • Fix for a problem that caused the Wi-Fi connection to temporarily switch off after prolonged use for some users.
  • Fix for a problem that caused first-party app updates to fail to install successfully for some users, leaving the apps in state where they cannot be launched.
  • Improvements for battery usage, Bluetooth connectivity, and OS reliability.

You can grab the update by checking for update in Settings > Update & security > Phone update.