Update release notes

Signed-off-by: Ciprian Hacman <[email protected]>

Author: hakman

docs/operations/images.md

@@ -20,11 +20,12 @@ image: ssm:/aws/service/canonical/ubuntu/server/20.04/stable/current/amd64/hvm/e
 
 ## Security Updates
 
-Automated security updates are handled by kOps for Debian, Flatcar and Ubuntu distros. This can be disabled by editing the cluster configuration:
+As of kOps 1.35, automated security updates are disabled by default to minimize the risk that node updates disrupt the cluster. Instead, we recommend updating instance group images on a regular cadence.
+To enable automatic security updates for Debian, Flatcar, or Ubuntu, edit the cluster or instance group configuration to include:
 
 ```yaml
 spec:
-  updatePolicy: external
+  updatePolicy: automatic
 ```
 
 ## Distros Support Matrix

docs/releases/1.35-NOTES.md

@@ -6,6 +6,7 @@ This is a document to gather the release notes prior to the release.
 
 # Significant changes
 
+* Aautomated security updates are disabled by default to minimize the risk that node updates disrupt the cluster. Instead, we recommend updating instance group images on a regular cadence. To enable automatic security updates, set `spec.updatePolicy=automatic`.
 * `bridge-utils`, `conntrack`, `pigz`, `libltdl` are no longer installed by default.
 
 ## Some Feature