desiredUpdate is an optional field that indicates the desired value of the cluster version. Setting this value will trigger an upgrade (if the current version does not match the desired version). The set of recommended update values is listed as part of available updates in status, and setting values outside that range may cause the upgrade to fail. You may specify the version field without setting image if an update exists with that version in the availableUpdates or history.
If an upgrade fails the operator will halt and report status about the failing component. Setting the desired update value back to the previous version will cause a rollback to be attempted. Not all rollbacks will succeed.