The Windows Insider Program isn’t the same as it was a few years ago. In late 2019, Microsoft leadership said Dev Channel (Fast Ring) is no longer tied to a specific Windows 10 release and we don’t know when a feature added in a preview build is going to ship to consumers.
Windows Insiders are currently receiving preview builds from “co_release” (co = Cobalt) and it’s believed to be part of the Sun Valley update. However, Sun Valley features have been stripped out of the preview builds by Microsoft. That’s because the company wants to unveil the whole new Windows Sun Valley UX/UI at an event on June 24 and surprise us.
A new support document (now edited) suggests that Microsoft could split this year’s fall Windows update into two versions, one for consumers and one for business and enterprise customers. This is mostly speculation at this point, but we do have reasons to believe in this theory.
As you can see in the above screenshot of support documentation, Microsoft appears to be testing two versions of the OS under the same codename 21H2 — 21H2 (minor update) and CO21H2 (CO = Cobalt, Sun Valley).
We’ve also spotted some hard evidence in a new preview cumulative update for Windows 10 version 21H1. Inside the KB5003214 (Build 19043.1023), we found references to version “21H2” and it’s now even possible to switch the current installation of May 2021 Update (version 21H1) to Build 19044 / version 21H2 by running some scripts.
This again suggests that the company wants to split the fall update into two parts, one for the consumers with Sun Valley changes and one for business/enterprises with quality improvements.
It is likely that the update for enterprises will be triggered by an enablement switch, just like the previous May 2021 Update.
- Sun Valley update with builds in 21K range for consumers, arriving later this year.
- Version 21H2 update with builds in 19044 range for enterprise customers, arriving later this year.
Microsoft will apparently continue to maintain the current look of Windows 10 for enterprise customers and the release of a minor service pack style update will give enterprises additional time to prepare their clients for Windows 11 / Sun Valley.
Enterprise doesn’t care about the new user interface and they’ll want to stick with Windows 10. As a result, Microsoft has been exploring ways that would give enterprise customers additional time to prepare for Windows 11 / Sun Valley and they’ll either split the update or allow businesses to turn off the new UI.
Remember that this is mostly speculation at this point and the information could be outdated, but the theory does make sense.