Questions to flow-to-disk queues in qpid broker

Issue

I have two questions to flow-to-disk queues:

• I observed that in some scenarios the flow-to-disk policy is not applied, meaning the queue accepts a message over its limits but the broker stores the message in memory and not in the journals. When this can happen?

• Is flow-to-disk policy applied also to transient (i.e. not durable) messages?