Microsoft did a (very!) bad job of communicating what was happening, but The Register has more information:
> He explained that both deactivations were executed as part of the Windows Hardware Program's account verification procedures.
> The company published a blog in October, giving devs a two-week warning that if their accounts had not been verified since April 2024, Microsoft would issue mandatory account verification notifications.
> "We worked hard to make sure partners understood this was coming, from emails, banners, reminders," said Davuluri.