News

Clock Winds Down on Windows 10 'Semiannual Channel Targeted'

• By Kurt Mackie
• 02/15/2019

Microsoft plans to make some changes to its Windows servicing lingo and management behavior when it releases Windows 10 version 1903 this spring.

At that time, the "semiannual channel (targeted)" (SAC-T) deployment milestone will be phased out, according to John Wilcox, a contributor to Microsoft Tech Community sites, in Microsoft's Thursday announcement. It will disappear from system settings after the next Windows 10 feature update release gets deployed by organizations. Wilcox had floated a partial description of these plans back in June.

This change will happen with Windows 10 version 1903, where the "19" indicates the year "2019" and "03" suggests the month. However, Windows 10 feature updates typically arrive one month later than the digits suggest, so the change likely will show up in April of this year.

After organizations deploy Windows 10 version 1903, they'll no longer see the SAC-T designation under Settings, Wilcox explained. SAC-T won't be seen by Windows Update for Business users, as well as users of System Center Configuration Manager and Windows Server Update Services, nor will it appear for organizations using "other management tools," he said.

Wilcox has previously argued that SAC-T was only relevant for users of the Windows Update for Business management scheme. Windows Update for Business is a collection of Microsoft technologies that lets IT pros use Group Policy settings to manage Windows 10 updates.

The SAC-T release was supposed to be a signal for IT pros to begin testing the Windows 10 feature update with a small group of end users in so-called "testing rings" before broadly deploying the new OS across an organization. In practice, though, organizations mostly just waited to deploy the SAC release that followed an SAC-T release, Wilcox previously noted.

Even though SAC-T will be going away, Wilcox said in the announcement that SAC-T "really is the actual release date" of Windows 10.

With the new behavior, Windows Update for Business users will just see the "SAC" designation, going forward, instead of SAC-T. Any deployment deferral settings that had been made by Windows Update for Business users will stay in effect, Wilcox promised.

In contrast, organizations that had timed their deployments on Windows 10 SAC releases, typically using tools like System Center Configuration Manager or Windows Server Update Services, will get a slightly altered update deferral experience after deploying Windows 10 version 1903. Microsoft plans to add "60 days to the configured deferral" for these SAC followers, Wilcox said.

Wilcox attributed the nomenclature change to Microsoft's need to align Windows Update for Business with Office deployment cycles. Office and Windows 10 both have channels update models. Apparently, SAC-T for Windows 10 was an exception.

For those needing more background information on this confusing change, Microsoft typically releases two main Windows 10 feature updates each year, which arrive in the spring and fall and have version numbers. From an OS deployment standpoint, these Windows 10 feature updates are called "semiannual channel" (SAC) releases by Microsoft. Under the current scheme, an SAC-T release would arrive before an SAC release, and would signal a time for organizations to test the new OS, and deploy it if it was deemed ready. But SAC-T will now get dropped.

However, Wilcox today said that the SAC-T release is Microsoft's actual OS release phase. Microsoft seems to have shifted its channel descriptions over time (which used to be called "branches"), and perhaps is doing some sort of simplification in this case, but it's been a confusing ride over the years.

This particular change mostly will be notable for Windows Update for Business users, though, Wilcox suggested.