Microsoft ended its free upgrade to Windows 10 offer for Windows 7 and 8 users in Summer 2016, but customers using assistive technologies are still able to install the new OS for free for now. Microsoft had yet to indicate if or when this offer would end at some point, but French website Ginjfo recently noticed that Microsoft updated the dedicated FAQ with new details.
According to the update, this free accessibility upgrade will expire on December 31, 2017, as you can see below:
Windows 10 introduced many new accessibility features for people with disabilities, including the screen reading experience with Narrator or the recently introduced built-in eye-tracking support. Microsoft takes accessibility very seriously, so if you use assistive technologies on your PC and have yet to upgrade, now is the time to do it. You can take advantage of the free upgrade offer by visiting the dedicated website and download Microsoft's Upgrade Assistant.