It has been three weeks since Microsoft was able to flight a fast ring build to Windows Insiders testing the Windows 10 Fall Creators Update on their PCs.

Microsoft had planned on flighting builds each of the last two weeks however, as the Windows Insider team explained over in the Feedback Hub last week, Builds 16262 and 16267 both had serious blocking bugs that resulted in a decision to not push those out to testers. According to Microsoft they would have resulted in very little testing and a lot of frustration on the part of testers being stuck in either upgrade loops or experiencing significantly reduced functionality.

So that last build everyone received for PCs, 16257, was released on 02 August and has undergone a lot of testing since then with three solid weeks of use by Insiders.

Based on the more than 65 documented fixes that are in today's build, 16273, and the likely untold number of tweaks/fixes that were applied under the hood and not documented, Microsoft also took advantage of the last three weeks to address a lot of stuff in this build.

This is good momentum because it is expected that Microsoft will wrap up development of the Fall Creators Update sometime in September and then likely begin its roll out on Patch Tuesday on 10 October.

You may recall that several weeks ago Microsoft also offered a limited number of testers an opportunity to Skip Ahead into the Redstone 4 (pre_release) branch for Windows 10. Those limited spots are already all taken and no one else will be offered the chance to get in that branch but in the next week or so the rs_release (Fall Creators Update/Redstone 3) and the Redstone 4 pre_release branches will head down their own development paths finally.

According to Microsoft's release notes for Build 16273, the pace of build releases for the Fall Creators Update will pick up with more fast ring builds plus some of them heading to slow ring for wider testing. The primary focus will be on addressing bugs and performance related issues. No new features will be added to the operating system at this point.

While the Fall Creators Update is the focus for Microsoft over the next few weeks, some work will continue with the fifth major feature update release, aka Redstone 4, in the pre_release development branch but those builds will no longer be in sync with the Fall Creators Update builds. At some point Microsoft will artificially advance the build number for Redstone 4 as it heads down its own full development branch leading to its release in the Spring of 2018.

Once the Fall Creators Update is released, then fast ring testers will be able to move over to the Redstone 4 pre_release branch to continue testing but they can also choose to remain on the final release of the Fall Creators Update and then move to testing builds later.

Bottom line is that the Windows 10 Fall Creator Update is just about ready and will be prepped for broad release over the next several weeks. That means more wondering when the final build will be marked as such and what that build number will be. If history is any teacher, Windows Insiders love to take their pokes at guessing when that happens and I suspect that will be the case this time around for the fourth major update to Windows 10 in just over two years since its initial release.

I am going to make my prognostication now and proclaim that the final build number for the Fall Creators Update will be in the range of 16290 and 16300.

What do you think?

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