Windows 11 prerelease previews will be full builds, not cumulative updates

Windows 11 prerelease previews will be full builds, not cumulative updates

Today, Microsoft released the first Windows 11 preview that came from the prerelease branch, specifically the rs_prerelease branch. Previously, all of the previews being tested have been for the initial release of the OS, so now the Dev channel has split off as Microsoft has been warning it would do.

Things are going to work differently this time though, and it’s a lot more like the Windows Insider Program worked before Windows 10. With these prerelease builds of Windows 11, the previews are going to be full builds of Windows, as opposed to the cumulative updates that we saw previously.

Here’s why. Microsoft did most of the building for Windows 11 in secret. By the time the company was ready to announce it, it was ready to ship from the release branch, specifically the co_release branch. The ‘co’ stands for Cobalt, and in line with the periodic table, the next version is Nickel. Once the previews switch over to release again, those builds are going to come from the ni_release branch, but now we’re getting ahead of ourselves.


The rs_prerelease (rs stands for Redstone, while we’re breaking things down, however much it’s irrelevant) branch actually isn’t supposed to be tied to a specific feature update. This is supposed to be the bleeding edge, and it’s what you sign up for when you enroll in the Dev channel. It’s for testing features, but specific updates, and that’s why sometimes, features will get pulled back before things switch over to a release branch. This is also why Microsoft has been sending out so many warnings to switch to the Beta channel, because for the past few months, there are a bunch of people that switched over to the Dev channel just to test Windows 11.

Their experience is going to change with today’s build. Dev channel users aren’t going to get the small cumulative updates that they saw with Windows 11 testing. These are going to be 4GB-ish builds that take longer to install, and often can cause your PC to be less stable. And yes, stability is an issue here, as Windows 11 testing up until this point has been relatively painless.

With today’s release of Windows 11 Insider Preview build 22449, you’ll probably notice that the watermark is back. This is the first time we’ve seen that on Windows 11, and again, this is because Windows 11 previews never actually came from a prerelease branch, at least not for the public. Expect to see this in future builds, and expect it to go away when we start seeing those ni_release builds mentioned above.

Also, you’re going to see bigger changes to the build number. You’ll be familiar with this if you were already a Windows 10 tester. If you’re new with Windows 11, you’d be expecting builds going forward. That won’t be the case. You’ll see build 22450 and up.

About author

Rich Woods
Rich Woods

Managing Editor for XDA Computing. I've been covering tech from smartphones to PCs since 2013. If you see me at a trade show, come say hi and let me ask you weird questions about why you use the tech you use.

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