This object is the threshold that triggers this specific association into its moderate, level-2 congestion state. Reaching this threshold means the association's backlog has grown past the mild-congestion point and is now significant enough to warrant heavier throttling, a meaningfully worse condition for that particular peer relationship than merely brushing level 1. An association regularly crossing this level-2 onset threshold during business hours indicates that specific peer relationship needs sustained throttling during peak load, not just an occasional brief slowdown.