Unscheduled & Unnotified GKE Node Pool Maintenance Caused Full Production Outage

Hi,

We encountered a critical and unacceptable incident on our production GKE cluster, where Google-initiated node pool maintenance/reboots occurred without any notification, resulting in a 2 hour 50 minute full production outage and severe business impact. We are not able to open a support case as we didn’t purchase this service. Are there any other ways to request an investigation/RCA?