You report to them your outage (https://support.google.com/cloud/contact/cloud_platform_sla https://support.google.com/cloud/contact/cloud_platform_sla) and the

You report to them your outage (https://support.google.com/cloud/contact/cloud_platform_sla https://support.google.com/cloud/contact/cloud_platform_sla) and then get monetary credits. e.g. for an arbitrarily-clicked service [1], it's 10% off for a month when they don't hit three 9s, 25% if they don't hit two 9s, and 50% off if they're below 95%. Which honestly isn't a very high uptime requirement, but there is a very clear process for getting payouts when they miss it. [1] https://cloud.google.com/filestore/sla https://cloud.google.com/filestore/sla