anchor.diff:    "plan_id": 		"plan-guid-here",
     "service_id": 	"service-guid-here",
     "app_guid":	 	"app-guid-here"
  -}' -X PUT
  +}' -X PUT -H "X-Broker-API-Version: 2.4" -H "Content-Type: application/json"
   </pre>
   
   In this case, `instance_id` refers to the id of an existing service instance in a previous provisioning, while `binding_id` is service binding id generated by Cloud Controller.
  
positive.code: ##### cURL #####
  <pre class="terminal">
  $ curl 'http://username:password@broker-url/v2/service_instances/:instance_id/
    service_bindings/:binding_id?service_id=service-id-here&plan_id=plan-id-here' -X DELETE
  </pre>
  
  ### Response ###
  
negative.code: <pre class="terminal">
  $ curl http://username:password@broker-url/v2/service_instances/:instance_id -d '{
    "plan_id": "plan-guid-here"
  }' -X PATCH -H "X-Broker-API-Version: 2.4" -H "Content-Type: application/json"
  </pre>
  
  ### Response ###
  