Windows 10: How to tell when a new build is ready for the public

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Windows 10

With the recent release of a new build of Windows 10, comes a few questions regarding how each public build is deciphered and released. Microsoft is constantly compiling new Windows 10 builds every day, however only a tiny subset of those builds will be seen by the public. To put that into perspective, out of hundreds of Windows 10 builds which have been compiled (and are still being compiled), the public has only received two builds.

So, how does Microsoft decide on which build is ready for public consumption? Well, it has everything to do with the development branches which are associated with the development of Windows 10. Builds which are released to the public only ever come from the fbl_release branch. This branch is dedicated to those outside the walls of Microsoft who aren’t developing the operating system, but are simply testing and delivering feedback.

The fbl_release branch follows similarly to that of the winmain development branch, which is the master development branch for Windows. More often than not, features that are newly available in the winmain branch are soon after available in the fbl_release branch too. The fbl_release branch is constantly getting updated with new builds, much like every other development branch, however that doesn’t mean we get access to every single build compiled.

There is a flight level system within the fbl_release branch which deciphers which builds reach the public. There is a high and low flight level system, and the low flight level is where the public gets access to new builds. You can keep an eye on which builds are marked as low with the help of, which is updated daily with new builds compiled internally at Microsoft. We’ll also keep you updated on when a new low level build has been compiled here at WinBeta.

So, now you know what the low flight level is. What’s the high one for? It’s still for testers, but it’s not for the general public. The builds which are labeled high are issued to Microsoft Partners, as Microsoft has stopped compiling builds in the fbl_partner range.

fbl_release builds are compiled daily, and most of which are labeled high. The few which are labeled low will get sent out to the public. Those who are wondering how the slow and fast lanes work within PC Settings on the Technical Preview, it’s pretty simple. Builds which are marked as a low level build will get sent out to those on the fast lane as soon as possible, whereas those on the slow lane will get access to the same builds, but at a slower pace.

Now the only question remains is what build do you think will get sent out to the public next? Leave us your ideas below!