Maybe there is something lost in translation. Certainly MAN-PEK is bookable with Hainan, but via BRU in co-op with Brussels Airlines.
Today, they have launched special offer flights MAN-PEK (via BRU) with special fares for travel in December. With that in mind, the chance of a non stop this year is Nil.
My money is still on Air China being first to launch, but when is another matter altogether.