Damn, this should have been my first post here. 10 years ago tomorrow, a bunch of Active Directory domains rolled back 10 years because an NTP server was giving the wrong year for an hour. And it broke EVERYTHING. Read the recovery process blog about it. https://techcommunity.microsoft.com/t5/core-infrastructure-and-security/fixing-when-your-domain-traveled-back-in-time-the-great-system/ba-p/255877