In April 2019, Microsoft began selling ESU plans to organizations, allowing them to receive critical security patches for three years past the 2020 retirement date—though this came at a significant yearly increasing cost.
The April 2019 timeframe was a critical junction for Windows 7 for several reasons: windows-7-all-in-one-apr-2019
Around April 24, 2019, Microsoft began deploying notifications to Windows 7 users warning them of the upcoming end-of-life date to encourage migration to Windows 10. In April 2019, Microsoft began selling ESU plans