plan_configuration (ElasticsearchPlanControlConfiguration)
Fine grained control over various timeout and fallback parameters
restore_snapshot (RestoreSnapshotConfiguration, required)
Allows for a snapshot of existing data to be applied from a local or remote repository once the new/upgraded cluster is up
strategy (PlanStrategy)
Describes various options that affect how we will perform a plan change. Only one of these can be specified at a time. The default is to let the system decide on the best method (currently it will always be 'grow_and_shrink' unless manually specified)