We've confirmed that all systems are back to normal with no customer impact as of 01/04, 10:20 UTC. Our logs show the incident started on 01/04, 09:20 UTC and that during the 1 hour that it took to resolve the issue some of customers may have experienced Alerting failure and Delayed alerts in East US.
Root Cause: The failure was due to an issue in one of our dependent services.
Incident Timeline: 1 Hour - 01/04, 09:20 UTC through 01/04, 10:20 UTC
We understand that customers rely on Log Search Alerts as a critical service and apologize for any impact this incident caused.
Initial Update: Saturday, 04 January 2020 10:53 UTC
We are aware of issues within Log Search Alerts and are actively investigating. Some customers in East US may experience may experience delayed alerts or Alerting failure during the impact .
Next Update: Before 01/04 13:00 UTC
We are working hard to resolve this issue and apologize for any inconvenience. -Madhuri