AWS Certificate Manager now provides certificate expiry …

Users can monitor “days to expiry” as a metric for ACM certificates through Amazon CloudWatch. An Amazon EventBridge expiry event is published for any certificate that is at least 45 days away from expiry by default. Users can build alarms to monitor certificates based on days to expiry and also trigger custom actions such as calling a …

https://aws.amazon.com/about-aws/whats-new/2021/03/aws-certificate-manager-provides-certificate-expiry-monitoring-through-amazon-cloudwatch/