Both benchmarks rose today, but at different speeds. WTI front-month gained 4.04% to $103.49 while Brent added 3.17% to $112.10, pulling the transatlantic spread back to $8.61 from the double-digit highs seen earlier this month. WTI simply closed the discount it had been carrying.

The compression rewrites the arbitrage from the US Gulf to China. WTI-linked grades—Lula priced off MEH, and some ESPO substitution routes—see their CIF East China cost rise with WTI, while Brent-linked grades (Dubai/Oman hooks) look relatively cheaper. Transshipment locks priced on the old spread need a full repricing.

For SNSUC's seven entrepot lines, the posted base = Brent × FX × 7.33 × grade, landing near ¥5,481/t today. WTI moves sit outside that formula but erode the delivered competitiveness of Atlantic-basin alternatives when WTI runs cheap.

The operational read is straightforward: re-stack ESPO and Lula CIF quotes against the Brent complex from today, and stop leaning on last week's spread habit. A 5-dollar swing in the spread on a 1-million-barrel cargo is a $5 million position error.