Windows 11 27H2 groundwork begins as Microsoft splits Canary Channel into two paths

Microsoft has split the Windows Insider Canary Channel into two separate development paths.
A new 29500 build series signals early platform work for Windows 11 version 27H2, expected in 2027.
Build 29531 is the first preview in this branch, focused on backend platform changes rather than features.

Microsoft is splitting the Canary Channel into two separate development paths as it begins early platform work for the next major release of Windows 11 (presumably version 27H2).

The company has introduced a second Canary track featuring builds in the 29500 series. These build numbers are higher than those associated with version 26H2, signaling that Microsoft is laying the groundwork for what is expected to become Windows 11 27H2, currently projected for fall 2027.

The change may seem unusual, but Microsoft has done something similar before. In past development cycles, the company used a “Skip Ahead” branch to let enthusiasts test early work for future releases. The new 29500 series serves the same purpose, even if it does not use the Skip Ahead name.

This time, however, users do not have to switch Insider settings to access the new path. Devices already in the Canary Channel will receive these builds as optional updates through the Windows Update settings.

Build 29531 is the first preview available in this new branch. It does not introduce new features or visual changes. Instead, it delivers platform-level modifications to prepare the operating system for future structural changes and to more clearly separate development tracks.

At the same time, the company will continue releasing Windows 11 26H1 previews in the 28000 series within the existing Canary path. These builds will continue to add new features and improvements.

Microsoft recommends that most Insiders remain on the 26H1 track for now. The 29500 series is focused on foundational engineering work and is expected to be less stable. The company plans to publish separate blog posts for each path to clarify progress and changes.

As with any jump to a higher build number, moving to the 29500 series prevents rolling back to a lower build without performing a full operating system reinstallation.

There is currently no indication that these builds are tied to “Windows 12.” All signs point to this being early development for Windows 11 27H2.

The split also helps explain Microsoft’s broader platform strategy. Windows 11 25H2 is built on the same platform as 24H2, allowing it to be delivered as a small enablement package rather than a full reinstall. Windows 11 26H2, expected later this year, is also based on the same platform as 25H2 and will follow the same enablement model. However, this won’t be the case for version 27H2.

The introduction of the 29500 series suggests that the release following 26H2 will require a new platform base. That typically means a full operating system upgrade, similar to the transition from version 23H2 to 24H2.

It is also worth noting that version 26H1, currently limited to devices powered by Qualcomm Snapdragon X2 processors, already includes platform-level changes. As a result, version 26H2 will not apply to systems running 26H1. Microsoft is expected to merge these development branches with the arrival of Windows 11 27H2 in 2027.

To download and install this first preview of Windows 11 27H2, enroll your devices in the Canary Channel in the “Windows Insider Program” settings under “Update & Security”. Once you enroll the computer in the program, you can download the build from the “Windows Update” settings, more specifically from Advanced options > Optional updates.