The Active Rating feature is in development. If you want to have access to the feature, submit a request at Zuora Global Support.
Zuora now provides a capability to actively rate or re-rate usage records in near real time for existing usage charge models. You can create one or more usage records through the REST API, or import usage files through the Zuora UI and REST API. After new usage records are submitted, you can also retrieve usage consumption information through the Zuora UI and REST API any time.