AWS Billing Bug Triggered False Cost Alerts in Slack, PagerDuty for Hours

An AWS estimated-billing bug caused by incorrect unit pricing inflated customer charges into the billions, triggering false budget alerts in automated cost-governance pipelines wired through Slack and PagerDuty. AWS confirmed actual charges were unaffected and paused estimate updates while reverting to accurate billing data. The discrepancy persisted up to 24 hours before detection, leaving FinOps teams without trustworthy telemetry mid-incident.