Updated

In case you hadn't heard, Microsoft's intent on giving away the newest version of its ubiquitous Windows operating system for PCs, Windows 10, to users of the previous three releases (Windows 7, Windows 8, and Windows 8.1). But although Windows 10 technically launches on July 29, not every eligible upgrader should expect it right away. That's according to a blog post in which Microsoft laid bare the update process, revealing that certain users, namely members of the Windows Insider beta program, enterprise users, and OEM partners, will have priority over others in Windows 10's staged rollout.

Windows Insiders get first dibs on Windows 10 when it releases, but that's for good reason -- they'll have to put up with any kinks and bumps that crop up. "Each day of the roll-out, we will listen, learn and update the experience for all Windows 10 users," Microsoft says. After the update system reaches some semblance of stability, the company says it'll start notifying people who've reserved copies "in waves," scaling up "slowly."

Business customers and OEM partners get the fast track treatment, too. Microsoft says distribution of Windows 10 Pro and Windows 10 Home will be available day one, with Windows 10 Enterprise and Windows 10 Education to follow on August 1. (Microsoft's published a feature comparison between the versions on the official Windows 10 website.) A finalized OEM release, along with a build for retailers to "assist customers with upgrades of newly purchased devices that were originally imaged with Windows 8.1," are also scheduled to go out shortly.

Microsoft's confident that, thanks to the deliberateness of this year's Windows release, everything will go smoothly. "In our testing of millions of systems, we're seeing full compatibility today with the vast majority of Windows 8x and Windows 7x systems," executive vice president of the Windows and Devices Group Terry Myerson wrote. "We are also rigorously testing and listening to every signal from our 5 million Windows Insiders on the quality and readiness of Windows 10."

To that end, Microsoft built in a mechanism that'll provide assistance with any problems that occur during individual installations. "If you're system is not ready yet for your upgrade to Windows 10, we will provide more details during the upgrade experience," Meyerson wrote. "In some cases, we will include contact information so you can follow up directly with an application provider or device manufacturer to learn more." Legacy programs, he says, will be the sticking point for most people. The solution? "Find alternative [programs] in the Windows Store after you upgrade," Meyerson wrote.