What's a good Upgrade Strategy for Enterprise AKS (Azure Kubernetes Service)

As per my understanding when dealing with AKS we're looking at 3 different components to upgrade/Update.

1) nightly Os security upgrades: reboot automated by Kured.
2) Node image upgrades : base images for the nodepool Vmss
3) kubernetes upgrades: the kubernetes version + the node image.
When working with an enterprise how do you automate all the 3 considering there is no fixed dates for the releases. Is a daily process (mannual/automated) looking for new releases the only way ?

Or is there a Microsoft recommendation/best practice for that, is there a routine that has worked for you guys in the past ?