Microsoft last month abandoned a four-year experiment during which it delivered multiple updates to Windows Server each yearandwill instead re-employ the upgrade-every-few-years practice it had codified for decades.

The change was the Redmond, Wash. company's greatest retreat yet from the accelerated release and upgrade regime of Windows, which it adopted first for the nameplate's client software and then later for Server.

"Starting with Windows Server 2022 there is one primary release channel available, the Long-Term Servicing Channel," Microsoft explained in documentation on Windows Server release tempo. "With the Long-Term Servicing Channel, a new major version of Windows Server is released every 2-3 years. Users are entitled to 5 years of mainstream support and 5 years of extended support."

In the same document that named the Long-Term Servicing Channel (LTSC) as the sole version of Windows Server 2022, Microsoft also implied - without putting it plainly - that the Semi-Annual Channel (SAC), the name for the release line that delivered two updates annually, is dead and defunct for Server.

Previously-issued SAC releases for Windows Server that still have support owed to them, including1909, 2004 and 20H2, will receive that support, Microsoft said. There will be no future SAC releases, however.

SAC no more

In June 2017, Microsoft announced it would begin to deliver SAC updates to Windows Server starting in the fall with the refresh designated as1709in the company's then-standardyymmformat. The idea, Microsoft said, was to synchronize Windows Server's release cadence with that of Windows 10 and Office 365, both of which were updated twice annually as part of an accelerated tempo begun in 2015 with the debut of Windows 10.

"We had two tracks of customers. One who wanted slow consistency and another who wanted continuous innovation," Microsoft said in a blog post four years ago as it described why it offered both LTSC and SAC release calendars and support lifecycles for Windows Server 2016.

Those rationales apparently no longer apply.

Instead, only an LTSC version of Windows Server 2022 - the next in line - will be offered to customers. As with other LTSC releases, Windows Server 2022 will be supported for a total of 10 years, the first five as Mainstream support, the second five as Extended support.

Although Microsoft has not revealed a definitive release date for Windows Server 2022, it has said that it would launch the upgrade in the second half of this year. A debut in October or November is most likely; the past two LTSC releases for Server rolled out during those months. (On Aug. 17, Microsoft said it plans to host the digital "Windows Server Summit" on Sept. 16; one the items on its agenda is "Get the latest news and announcements about Windows Server 2022." It seems fair to expect a release date to be among the announcements that day.)

With the Server move, Microsoft comes full circle

By dropping the SAC releases, Microsoft has come full circle; it has returned Windows Server to its pre-2015 cadence of upgrading every three or four years. (Windows Server 2016 to Windows Server 2019 to Windows Server 2022, three-year intervals; Windows Server 2008 to Windows Server 2012 to Windows Server 2016; four-year intervals.) Support has been formalized again at 10 years and 10 years only; there's no longer SAC support cycles of 18 months. And the former practice of issuing new features and functionalities only at that three-to-four-year tempo has been restored, with LTSC releases only - in other words, every two or three years - not, theoretically at least, every SAC release producing something new and shiny. (That was never the reality of SAC releases.)

Microsoft has turned tail from its vaunted Windows-as-a-Service (WaaS) in other ways of course, notably with Windows client itself. With the announcement earlier this summer of Windows 11, and the information about its new servicing strategy as well as maintenance mechanics, it's obvious that WaaS is a meaningless term for something Microsoft no longer delivers.

Even so, Windows 11 and its still-current-and-supported forerunner Windows 10, haven't gone as far as Windows Server in reversing the last several years. Windows client, for instance, will keep SAC releases (as well as LTSC releases) and less-than-10-year support lifecycles. (The longest SAC support cycle is 36 months, up from 30 months, for Windows Enterprise and Windows Education.)

But if Microsoft is practicing a last-in-first-out policy with Windows, then Server, which followed Windows clientintoWaaS and now, will be the first out, may be a harbinger for how the client changes down the line.