Today's session was a split in the dollar. The yuan firmed as USD/CNY fell 0.0195 to 6.6687, while the yen and won both softened: USD/JPY rose 0.1205 to 157.86 and USD/KRW rose 0.1613 to 1359.9. The euro softened too, with EUR/USD slipping to 1.1205.

For transshipment, exchange rates are harder to watch than oil because a cargo from signing to payment can span two or three weeks. A firmer yuan lowers the RMB landed cost, which helps domestic refinery clients; a weaker yen and won make the Japan or Korea transshipment or sourcing leg more expensive when counted in local currency.

Operationally, for lines with a Japan or Korea transshipment leg scheduled this week, pull the exchange-rate sensitivity out and look at it on its own rather than only tracking Brent and WTI. Where an offshore transfer can be completed in one currency at one bank, lock the rate window.