Yesterday saw this same build go out those on the Insider program, but today's release is a general one for what looks like all new phones sold with Windows 10 Mobile build 10586.
As confirmed in our forums, users are getting the update even though they are not enrolled in the Insider program marking this as the first test of Microsoft's Windows as a Service (WaaS) model.
Matching this update for Mobile is today's cumulative update for the desktop. That OS refresh also brings those PCs up to 10586.29 making this one of the first times both PC and phone get the same update on the same day.
Today's update is even more significant as AT&T is evidently letting this update go to their Lumia 950 with no interference.
This result lends credence to the idea that Microsoft specifically chose carriers that would let them have unfettered update abilities to their new Lumias for customers. Perhaps Verizon, Sprint and T-Mobile would not allow such access that only rivals Apple.
What's new in build 10586.29
- You will see additional improvements in upgrade experience, including devices with limited free space, map rendering on update, and RCS enabled device settings.
- Improved application backwards compatibility for Windows Phone 8.1 Silverlight applications.
- Edge performance and stability has been improved. Auto-completion has been updated to allow user to more easily edit the end of the URL in the address bar.
- Additional Bluetooth stability improvements.
- We have resolve issues on switching the active cellular connectivity profile on Dual SIM devices.
If you do not see the update just yet give it some time as this make take a few hours to hit all servers worldwide.
Source: Windows Central Forums; Thanks, everyone, for the tips!