Did you have paged messages on the address when it happened? Just trying to understand the scenario.
The scenario is that we have JMS queue that feeds messages into a JMS topic by means of a core bridge. The topic is configured to block when address is full and the queue is configured to page. The idea being that when paging occurs on the queue we can institute diverts on the topic, move messages out of the largest topic subscription into a new holding queue and the transformer on the core bridge will alter the message headers to cause the diverts to cause messages to 'split' into two: one copy for the topic minus the offending subscriber's token and the other copy to go into the subscriber's holding queue.
The move part of this had failed in as much as it had not managed to move some 270 of 9000 messages (possibly because they were being delivered to a consumer who had failed mid-delivery). The outcome was that the topic was still blocking despite having a lot fewer messages in it than the memory parameters would allow.
We would have had paged messages on the JMS queue. The JMS topic was configured as blocking, so its address would not have had paged messages.