When using the multi-version client, those client versions that aren't compatible to the cluster are not made aware of changes to the coordinators. This can cause a problem if, for example, the entire cluster is migrated to new hosts and then the cluster is upgraded. Any clients that had setup the multi-version client prior to the migrate would cease to work at the time of the upgrade.

This behavior can currently be avoided (or remedied) by bouncing any clients using multiple versions via the multi-version client API anytime after the coordinators are changed.