Does eks use latest AMI version on termination of any node on restart of the node

Which version of the operating system is used is based on what is stored with the AMI of the underlying launch template of the Managed Node Group. No changes will be made to that process automatically without taking one of the steps below. AMIs are immutable. They can not receive OS updates without creating a new AMI. Managed Nodes Groups can be updated if a new version is available (https://docs.aws.amazon.com/eks/latest/userguide/update-managed-node-group.html). You can also customize the launch template (and therefore the AMI) of your managed node group (https://docs.aws.amazon.com/eks/latest/userguide/launch-templates.html). If you will customize, a common better is to link EC2 Image Builder with your Launch Template: https://docs.aws.amazon.com/imagebuilder/latest/userguide/dist-using-launch-template.html.