Microsoft 365 Principal SRE here. I can provide some context. At approximately 21:40 UTC, an engineer deployed a routine configuration change to Azure Front Door that inadvertently redirected our authentication traffic to a SharePoint site last updated in 2017. We immediately initiated a rollback, but the rollback pipeline requires MFA approval through Microsoft Authenticator, which is currently waiting for a Conditional Access policy evaluation from the same infrastructure we're trying to restore. We have a break-glass admin account, but unfortunately its password is stored in a OneNote notebook on the affected tenant. Our on-call engineer attempted to bypass the issue using PowerShell, but the required module was deprecated last Tuesday, and its replacement requires a P2 license. We then opened a Sev A ticket with Microsoft Premier Support. They responded asking us to run sfc /scannow and provide a screenshot. The prolonged recovery is primarily due to our change advisory board requiring a Teams meeting to authorize the rollback. The meeting organizer is stuck in the lobby, and the only person authorized to admit him was laid off in June. Current mitigation involves migrating affected users to Microsoft 365 E5, which should resolve the issue from a revenue perspective. We have identified the root cause as customer misconfiguration. Next update in 30 minutes, assuming someone can get Outlook working.