We are excited to announce that Amazon ElastiCache for Redis now supports self-service updates. This feature allows you to apply service updates at the time of your choosing and track the progress in real-time. You now have the visibility and control on service updates to maintain HIPAA-eligibility, PCI-compliance or FedRAMP-authorization on your ElastiCache for Redis cluster on a schedule that best fits your business needs.

When service updates applicable to your Redis replication group(s) become available, we will notify you via multiple channels including ElastiCache console, Emails, Amazon Simple Notification Service (SNS), AWS Personal Health Dashboard (PHD) and Amazon CloudWatch Events.
You can start using self-service updates via the ‘Service Updates’ page in the Amazon ElastiCache console, AWS ElastiCache API and AWS CLI. The self-service updates feature is available in all AWS Regions for Redis replication groups running engine versions 3.2.6 and later. For more information about this feature, see ElastiCache for Redis Service Updates

from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/06/elasticache-self-service-updates/