Google Kubernetes Engine: Kubernetes 1.35 end of extended support

At the end of extended support, GKE does not provide any patches for security fixes, and the minor version is considered unsupported. GKE upgrades clusters still running it to the next minor version.

• The upgrade happens regardless of the cluster's use of deprecated features or APIs.
• Maintenance exclusions cannot be configured past this date, except as a temporary, emergency measure with the "No upgrades" scope.
• That exclusion can delay the upgrade for up to 90 days after the end of support date. Google does not recommend it.
• Dates in the GKE release schedule are updated monthly and subject to change.

1. Google does not recommend enrolling a cluster in the Extended channel without plans to move to the next minor version, because GKE eventually upgrades the cluster to newer minor versions.
2. Around 2 months before the end of extended support, GKE begins upgrading clusters in the Extended channel to the next minor version, unless the cluster is using deprecated features or APIs.
3. Maintenance exclusions can prevent minor version upgrades until the end of extended support. A temporary, emergency exclusion with the "No upgrades" scope can delay the upgrade for up to 90 days after the end of support date. After that exclusion expires, GKE upgrades the cluster.
4. At the end of extended support, GKE upgrades all clusters still running the minor version, regardless of blocking issues. See GKE minor version lifecycle.