This object is the threshold that triggers this specific association into its most severe, level-3 congestion state. Being the last line before the association enters its heaviest throttling, a specific peer relationship crossing this threshold is in real danger of queued signaling messages building up faster than they can be delivered, risking delay on delay-sensitive call-control traffic to that peer. An association hitting this level-3 onset threshold during a traffic spike to one specific MGC, while its sibling associations to other peers stay well below it, isolates that one relationship as needing urgent capacity attention.