When using AWS Elemental MediaStore as your live streaming origin, you can now configure a Transient Data Policy on your container via the Object Lifecycle Policy API, which will remove an HLS manifest if it has not been recently updated. This enables players to automatically switch from a primary origin to a backup origin with no additional coding or setup. Customers with redundant encoding pipelines previously had to perform complicated configuration downstream of the origin to ensure manifest freshness. With Transient Data Policy, customers can leverage native HLS behavior to perform origin switch-over.

from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/09/aws-elemental-mediastore-now-supports-stale-manifest-deletion/