The scenario:
1) two durable subs on a topic (subA and subB),
2) subA consumes the message and acks in 2 Phase commit,
3) after XA prepare on SubA the broker restarts.
4) On reconnect, subA cannot get the prepared messages till rollback or not at all on commit, (all good so far)

The Problem:
If SubB tries to consume the message after the broker has restarted, it cannot get its copy of the message.

Reason:
Tracking of recovered acks by messageId is store wide, so that it effects all subs if one sub has a pending prepared ack. The tracking of prepared pending acks needs to be per durable sub.

Upstream issue https://issues.apache.org/jira/browse/AMQ-7311