I have a HA group formed of three nodes. I stop one the nodes using the Stop button on its VHN tab. The node stops correctly and temporarily detaches from the group leaving the two remaining nodes providing service.
If I then observe the group from the VHN tab of either of the two remaining nodes, I see the role of the stopped node as UNKNOWN (correct behaviour), but the replication transaction id is still populated (with the last known value). This information is stale and might mislead the user. In the case where the group has suffered a network partition the value could be wrong.
A node should discard the remote replication transaction id when it looses contact with the remote node and should display N/A.