Microsoft is adding three more months to the period during which customers purchasing Windows 10 S devices will be able to upgrade to Windows 10 Pro for free.

Earlier this year, when introducing Windows 10 S, Microsoft officials said users would have the option of upgrading from Windows 10 S to Windows 10 Pro for free until the end of calendar 2017.

In a September 5 blog post about Surface Laptop colors, Microsoft slipped in a note that extended the free-upgrade period until March 31, 2018.

Windows 10 S is a version of Windows that limits users to running only Windows Store apps. Microsoft officials are pitching this version of Windows 10 as being more secure, streamlined and better performing than other Windows 10 variants. To entice users to give Windows 10 S a try, Microsoft added an option to allow them to upgrade to Windows 10 Pro if they decided they needed apps that weren’t available in the Store.

Microsoft officials originally said after December 31, anyone other than students who had Windows 10 S would have to pay $49 to move to Windows 10 Pro. (Officially, Microsoft refers to Windows 10 S as a “mode” of Windows 10 that runs on top of Windows 10 Pro.)

Microsoft’s blog post mentioning the change in the upgrade offer makes it seem that officials realized some might be reticent to buy a Windows 10 S device in the latter part of this year without the assurance of a potential free escape hatch:

“For those that find they need an application that isn’t yet available in the Store and must be installed from another source, we’re extending the ability to switch from Windows 10 S to Windows 10 Pro for free until March 31, 2018. We hope this provides increased flexibility for those people searching for the perfect back-to-school or holiday gift.”

I also wonder if the promised-but-still-missing Windows Store version of iTunes and/or other apps may have anything to do with the postponement.

Microsoft officials also announced today that its Surface Laptops are now available in more colors in more countries. The September 5 blog post has the details.

Microsoft made Windows 10 S the default operating system loaded on its premium Surface Laptops when it introduced them earlier this year.

Even though its initial pitch for 10 S out of the gate was as an operating-system suited for education and Chromebook-compete, Windows 10 S is for business users, too, officials said. Microsoft told Inspire partner show attendees that 10 S is well suited for experiences like mobile-computing work, frontline user work, plus embedded usage in kiosks and signs.

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