External data source drift SHALL be monitored where system behavior depends on external data feeds.

Compliance is evaluated through analysis of continuous monitoring telemetry collected over a defined observation period during live or simulated operations.

This is a conditional control. Non-compliance with this ACR may result in conditional certification with a mandated remediation period. The Authorized Verification Body will specify the remediation timeline and required evidence for the condition to be cleared. If remediation is not completed within the specified period, the conditional certification will be revoked.