Microsoft today has released Windows 10 build rs1_release_11082.1000 to those on the Insider Fast Ring. This update is the first branch of the so-called Redstone release and marks the first step beyond the current Threshold builds of Windows 10 in the past.

For those on the Insider program who are enrolled in the Fast Ring you can check for an update under Windows Update (Settings > Update & Security > Windows Update > Check for update) to grab the latest version.

According to the blog post:

"With this build, you won't see big noticeable changes or new features just yet. Right now, the team is focused on product improvements based on the feedback we're hearing on the November update to Windows 10. This includes the changes that have also been going out as cumulative updates through Windows Update on your PCs running the Windows 10 November Update as well as on phones running Windows 10 too. We're also working on some structural improvements to OneCore, which is the shared core of Windows across devices. Essentially, OneCore is the heart of Windows, and these improvements to OneCore make building Windows across PC, tablet, phone, IoT, Hololens and Xbox more efficient. We're doing some code refactoring and other engineering work to make sure OneCore is optimally structured for teams to start checking in new features and improvements in the new year."

Source: Microsoft