At the moment the 'size' parameter is in the example ActiveMQArtemis custom resource, however it is not read, nor utilized. This should serve the purpose for the number of brokers that are scaled up when the custom resource is installed, and should be checked on reconciliation pending completion of ENTMQBR-2513

The name 'size' may not be the most correct, however the naming can be adjusted once the functionality is in place.