Both patch version (e.g. 1.20.13) and (e.g. 1.20) are supported. When is specified, the latest supported GA patch version is chosen automatically. Updating the cluster with the same once it has been created (e.g. 1.14.x -> 1.14) will not trigger an upgrade, even if a newer patch version is available. As a best practice, you should upgrade all node pools in an AKS cluster to the same Kubernetes version. The node pool version must have the same major version as the control plane. The node pool minor version must be within two minor versions of the control plane version. The node pool version cannot be greater than the control plane version. For more information see upgrading a node pool.