The ShardingCatalogClient offers a set of API methods to retrieve placement metadata on a namespace at a given point in time.

Today, these methods are implemented as an local/remote aggregation query that inspects the content of config.placementHistory.

Nevertheless, such implementation may return inconsistent results during the execution of a setFCV command from/to version 7.0.

The problem could be avoided if the logic accessing the config catalog where under exclusive control of the config server.