Windows 10 Mobile Build 10586 available for Insiders
The same build is on Lumia 950 and Lumia 950 XL
Microsoft has finally released the new test version of Windows 10 Mobile to all users who have joined the Windows Insider program. This build has been pre-loaded on the Lumia 950 and Lumia 950 XL, and Microsoft will release it to the general public in the coming weeks, so we can call it RTM.
As a RTM build, Windows 10 Mobile v.10586.11 packs a number of bug fixes and performance improvements over the previous builds. Microsoft has fixed pretty much everything that does not work in build 10581 – the corrupted start screen; default save location issues; resuming screens and more. Users can move apps to the SD card without seeing the apps to crash. There are also improvements in Messaging + Skype app, and in the Store app – downloading apps is more reliable.
Important notes:
If you upgrade from build 10581 after doing a factory reset, your phone will go into a reboot loop after the upgrade to 10586. You can recover the phone using the hardware key combination to reset your phone, but our advice is to roll back to Windows Phone 8.1 before upgrading to build 10586.
If you upgrade from build 10581 without doing a factory reset, or from previous builds, including Windows Phone 8.1, then you are safe and your phone won’t go into a reboot loop.
Source: Microsoft