Placing 6 through 8 September side by side, the heavy-product complex completed a full repair cycle.

On the 6th, fuel oil front-month fell 2.04% to RMB 3,793/t, the largest single-day drop of the week, while Brent edged up 0.43% — a clear divergence read at the time as softening bunker demand. On the 7th, fuel oil rose just 0.21% to RMB 3,880/t while bitumen gained 2.11% to RMB 4,879/t, widening the slope gap further and confirming demand-side divergence.

On the 8th the structure reversed: fuel oil printed RMB 3,988/t, up 4.97%, and bitumen printed RMB 5,002/t, up 4.38%, both at new highs. Cumulatively, fuel oil recovered roughly 5.1% from its low on the 6th and bitumen advanced roughly 5.4% from its level on the 6th, with the two curves shifting from divergence to resonance.

Resonance means the driver moved from each product’s own demand side back to a shared cost side. Brent gained roughly 3.3% cumulatively over the same three sessions, making feedstock cost the dominant variable and overriding the separate demand stories of shipping and infrastructure. That in turn validates reading the 6th’s isolated fuel oil decline as a sentiment pullback rather than the start of a trend.

The procurement implication is clear: in a cost-push phase, strategies that wait for inter-product spreads to revert fail, because both curves move together. Bitumen has entered its rigid peak-season demand zone, where higher prices do not deter liftings. The fuel oil restocking window largely closed after the jump on the 8th — the extended window South China bonded bunker buyers saw on the 6th has disappeared.

Sources: INE / SHFE / DCE front-month futures and FX quotes (delayed), synced via the SNSUC market module. For reference only, not trading advice.