Transit AA subscribers can be persistent within a single node, because in some cases, there is not a dual-node BNG subscriber redundancy configuration. This allows a single node that has dynamically created transit subs to retain the subscriber state, context, and statistics across a node or ISA reboot.
If dynamic transit AA subscribers are released, renewed, or otherwise changed during an outage or reboot of a transit AA node, the sub manager notifies the transit node of these changes.
Prefix transit subs are not affected by persistence because they can only be statically configured.