Microsoft today promoted its Windows 10 August upgrade to the Current Branch for Business release track, putting the "Anniversary Update" in the queue for automatic download and installation on enterprise PCs.
The move will also set in motion a two-month countdown clock on support for the original mid-2015 version of Windows 10.
"Windows 10 1607, also known as the Windows 10 Anniversary Update, has been declared as Current Branch for Business (CBB) and is ready for deployment," Michael Niehaus, a director of product marketing, said in a post to a company blog that used similar wording to the first upgrade to the CBB. In April, Microsoft moved the November 2015 upgrade to the corporate delivery track.
Microsoft issued the Anniversary Update Aug. 2, even though its numerical designation of 1607 referred to July (07) of this year (16).
The upgrade will be released in January through Windows Update, Windows Update for Business and Windows Server Update Services (WSUS), Niehaus said. Microsoft-made or third-party management tools, such as Microsoft's System Center Configuration Manager, will be able to roll out 1607 to PCs on the CBB track once Microsoft's "publishes" it on WSUS.
With the promotion of 1607 to the CBB, the clock began ticking on the end of support for the initial Windows 10 release, dubbed 1507 to mark its July 2015 launch. Microsoft has pledged to support at least two CBB builds concurrently, which means that at the release of N+2, where N equals the oldest version, the company starts a 60-day-or-so countdown. At the end of the 60 days, N drops off the support list.
With 1607 shifted to the CBB, N equaled 1507, N+1 represented 1511 and N+2 equaled 1607. That meant 1507 will be shut off from security updates in March, probably as of March 14, that month's Patch Tuesday. After that date, PCs assigned to the CBB must be updated to at least 1511 to continue receiving vulnerability fixes.
Windows 10 users can check which release builds are supported by referring to this page on Microsoft's site.
Microsoft's original release and support strategy, which it laid out last year, was predicated on a three-times-a-year cadence, with new builds issued about every four months. While the company maintained that tempo in 2015, it soon signaled that it would not be matched in 2016. Instead, only one Windows 10 release shipped this year.
In 2017, however, Microsoft has committed to release two upgrades. If it ships the first in March, 1511 -- the November 2015 build, and the new N -- would fall off the CBB support list around next September.
According to some industry analysts, the Anniversary Update, aka 1607, will be the version most corporate customers use to migrate their PCs to Windows 10. Due to timing on the part of both Microsoft and enterprises, Windows 10's support cycles, and old habits, 1607 "will be what they roll out," said Gartner's Steve Kleynhans this summer.
Under Microsoft's most likely shipping schedule for 2017, version 1607 will remain on patch support until April or May 2018.