Should you be the owner of an Alcatel OneTouch Fierce XL on T-Mobile in the U.S., you'll be pleased to learn of a new update that should hit your smartphone. Windows 10 Mobile build 10586.164 is the update that is reported to be hitting the Windows mobile device.
If you haven't received a notification yet, fear not as you can manually check for update by heading into settings > update & security > phone update and hit "check for updates". As for what's included in the update, T-Mobile has yet to supply a change log on the company's website, but Microsoft has said that build .164 is pretty much identical to the retail .122 build.
Let us know in the comments if you've received the update!