Currently secondaries are refreshing sharding metadata only when receiving a query with the sharding version (from mongos or via mirrored reads).

This means that if a secondary that did not receive any query become primary (for example an hidden node that is made primary after a rs config change) will need to full refresh the metadata and therefore possibly heavily impacting the query performance.

Would be nice to force metadata refresh of all secondaries every time there is a metadata change (like is happening on the primary) and not wait for an upcoming queries