Spot discounts for high sulphur fuel oil (HSFO) narrowed slightly on Friday, while very low sulphur fuel oil (VLSFO) retained downside risk. Singapore’s cash differential for 380-cst HSFO was pegged at a narrower discount of $1.85 a metric ton, with inter-month spreads recovering slightly. Meanwhile, spot VLSFO differentials remained below discounts of $1 a metric …