On October 22, the fuel oil front-month settled at CNY 4,911/t, up 2.40% on the day — roughly 4.5 times the 0.53% gain posted by bitumen at CNY 4,533/t. The fuel-oil/bitumen spread flipped back to positive at +CNY 378/t, tilting the refinery residue-yield balance toward fuel oil.

The driver sits in residue routing. VLSFO blending demand recovers into the fourth quarter while HSFO holds a floor from scrubber-fitted vessels; both compete for residue and push fuel oil to the front. Bitumen, by contrast, is capped by the road-construction off-season and slower social-inventory drawdown. The VLSFO/HSFO dual track set by the IMO2020 sulphur cap is the anchor of this ratio.

For transfer traders, a positive FO/BIT spread reopens the margin window between bonded bunker fuel and coking feed. The same parcel of straight-run Middle East fuel oil can either feed VLSFO blending or delayed coking for petroleum coke, with the crossover sitting near +/-CNY 400/t. Today's +CNY 378 is already close to that line; if fuel oil keeps leading bitumen next week, coking economics will compress further.