That's news to me. The free upgrade period is over[1].
The only free Windows 10 upgrade is the one for users of assistive technologies[2]. Of course, you can just pretend to be a user of assistive technologies, but I'm uncertain about the legal ramifications of doing so, regardless of whether or not you'll be caught.
Additionally, Windows 10 silently accepts Windows 7 and 8 product keys[3], but the legal situation is equally nebulous in the face of [1].
The only free Windows 10 upgrade is the one for users of assistive technologies[2]. Of course, you can just pretend to be a user of assistive technologies, but I'm uncertain about the legal ramifications of doing so, regardless of whether or not you'll be caught.
Additionally, Windows 10 silently accepts Windows 7 and 8 product keys[3], but the legal situation is equally nebulous in the face of [1].
[1] https://support.microsoft.com/en-us/help/12435/windows-10-up... "Is the Windows 10 free upgrade offer still available?" => "The Windows 10 free upgrade through the Get Windows 10 (GWX) app ended on July 29, 2016."
[2] https://www.microsoft.com/en-us/accessibility/windows10upgra...
[3] https://www.bleepingcomputer.com/news/microsoft/you-can-acti...