CooperativeStickyAssignor rebalancing on Alpakka consumer

Hi, new to Akka and Alpakka here, got some question about consumer rebalancing behavior

Will Alpakka consumer still obey the rebalancing protocol that is configure in the underlying Kafka client side? I saw that the documentation only mentions about all partitions being revoked on Consumer rebalancing event (React on Partition Assignment • Alpakka Kafka Documentation) which is based on eager rebalancing protocol.

But if cooperative rebalancing protocol is used (CooperativeStickyAssignor (kafka 2.5.0 API)), will all partitions still all be revoked and reassigned, or some partitions can retained on existing consumer like what the protocol is actually intended.