If a resource is moved to another endpoint and the initial endpoint is still reachable, then it is efficient for it to 
act as the primary resolver. When a client sends a stale EPR,the service should repond with the new EPR rather than re-
directing the client to make another unecessary call to a resolver. 
The above is in addition to either the old endpoint or the new endpoint making a registration in one or more resolvers. 
The resolver is used when the endpoint is no longuer reachable..