Microsoft won't have all the pieces in place for its Windows Update for Business (WUB), a new service touted in May that's designed to ease corporate concerns about Windows 10's maintenance model, until sometime in 2016, according to a company manager.

"Some of it will be available now, some of it will be delivered in subsequent releases. So it's definitely a work in progress," said Michael Niehaus, a senior product marketing manager, in one of several videos shown last week in a series on the firm's virtual academy website.

Niehaus was talking about Windows Update for Business, or WUB, a service Microsoft announced nearly four months ago. WUB, an offshoot of Windows Update, the consumer-grade service that has been central to Windows' 20-year-old update model, was pitched then as a way for companies to manage the perpetual refreshes of Windows 10.

The reference to several releases -- when Windows 10 will be updated every four to six months, according to Niehaus -- would push a completed WUB deep into next year.

When Terry Myerson, then the head of Windows, broached the subject of WUB in May, he painted the service only with the broadest strokes, saying that it would be available free of charge to owners of Windows 10 Pro and Windows 10 Enterprise. But he omitted details about its inner workings or its availability timeline.

Niehaus filled in some of the blanks, or better put, confirmed what another Microsoft marketing manager said in an April 30 webinar for the Redmond, Wash. firm's partners. That manager, Helen Harmetz, had spelled out the basic tenets of WUB; how it is linked to the "Current Branch for Business" (CBB), the update track Microsoft wants to see most corporate Windows 10 devices adopt; and what penalties would be levied on organizations that didn't keep their machines' operating system up to date.

Harmetz's comments are the first to go public that define the delays built into the CBB and available only to that branch: Four months after a feature-and-functionality update reaches consumers on the Current Branch (CB), systems on the CBB will start receiving the same update. The delay, said Microsoft, gives it a huge pool of testers that will theoretically uncover bugs, allowing the company time to correct them before delivering changes to the crucial business audience.

The four-month delay of the CBB can be enabled by checking the "Defer upgrades" box in the advanced section of Windows 10 Pro's or Windows 10 Enterprise's Windows Update settings. "You check that box and you instantly get a four-month delay," said Niehaus. IT administrators can also use Group Policy templates to remotely enable CBB on large numbers of PCs.

For longer postponements, customer IT staffs must use something other than WUB to process upgrades and updates, specifically Windows Server Update Services (WSUS), Microsoft's System Center Configuration Manager (dubbed "Config Manager"), or a third-party patching product. Harmetz made that clear in April, but in last week's video, Niehaus only said -- several times -- that customers on the CBB will be able to delay an update/upgrade for up to 12 months.

The dozen months is a combination of the four-month stretch during which PCs on the CB must adopt the upgrade plus the four-month maximum delay of the CBB plus another four-month delay available to businesses that rely on WSUS, Config Manager or another patch management platform. Harmetz had explained that last third of the 12-month span, but Niehaus did not. In itself, that wasn't surprising, since Microsoft has been hesitant to disclose information about some of Windows 10's underpinnings, a trait it's taken heat for from analysts and customers.

WUB, critical to the middle third of the 12-month term, is only partially complete at this point, Niehaus acknowledged. Among the pieces included in the initial release, he said, are an optional peer-to-peer delivery mechanism -- which has come under fire for its bandwidth sharing -- and the "Defer upgrades" option that drops a PC into the CBB.

More is to come, Niehaus pledged. "We do expect to provide additional features over time to let you define your own rings, to let you do scheduling and maintenance windows, and other capabilities like that," he said in the video. "We will be beefing up that as we move forward down the line."

"Rings" is another term that Microsoft recently added to its update lexicon. The CB and CBB tracks will be further subdivided into multiple tempo rings -- Fast and Slow are best known from the Windows Insider preview channel that's been running nearly a year -- but it's declined to specify the number, name and cadence of those rings.

Niehaus did not illuminate customers there, either, but his mention of rings hints that Microsoft might not define standard rings in WUB for the CBB deployment schedule, and will instead give IT administrators tools so that they can craft their own rings to segment their PC populations into discrete groups.

"We want to enable capabilities where you can build your own rings inside of [Current Branch for Business] and be able to do a phased deployment inside of your organization," said Niehaus.

His commentary also touched on Microsoft's WUB philosophy, and in some ways confirmed analysts' earlier expectations that the service would eventually replace WSUS and Config Manager. "A longer term goal, is really to provide kind of a cloud-based equivalent to what you would do today using WSUS or Config Manager," he said. "We will be adding more capabilities to Windows for Business to make it roughly the equivalent [of WSUS and Config Manager], but without you needing the infrastructure yourselves."

Microsoft's no-rush attitude toward WUB and the CBB reflects the reality of Windows 10 adoption. Although millions of consumers have upgraded their Windows 7 and Windows 8.1 devices to Windows 10 by accepting the firm's free offer, most businesses will move slowly to the new OS. Analysts anticipate that the corporate push to Windows 10 won't be meaningful until 2017, and that Windows 7 will remain the dominant enterprise OS for at least the next three years.

By Redmond's schedule, the first feature-and-functionality upgrade will hit consumers on the CB this fall: Four months after Windows 10's debut would be late November. If Microsoft hews to the four-month delay, that would mean the first upgrade would land on the CBB in late March 2016.

Or maybe even later: By Niehaus' description, Windows 10's release cadence could be slower than three times a year. "The actual development time varies, but it could be four to six months spent on a new upgrade, working on new capabilities, that will then be released to the Current Branch," Niehaus said.

Previously, analysts like Gartner's Michael Silver and Steve Kleynhans had predicted an every-four-month upgrade for Windows 10, the interval that Harmetz also touted. Niehaus' talk of four to six months, however, may reflect Microsoft's realization that it will not be able to produce on the fastest pace.