On the new create collection path if we find a NotPrimaryError or a ShutdownError category we bubble up the exception to the router, however, given the fact that we're working on the DDLCoordinator and we're handling this behavior on the completion of the operation, it is better to handle it locally on the _commit function, leveraging that we made the writes to the config server idempotent operations. We could for example use a retryable write, or simply adding a loop to always retry if the response is an error of any of the mentioned categories.