It is indeed good.
HU have also protected 4 slots this winter too. It's currently down to make CAN daily, but personally I think it could be for an eventual 4 weekly PVG should Air China give in with the rights.
Or, given the other HNA airline, Tianjin Airlines, has dropped plans to serve Xi'an from Gatwick, so, could the route be heading north but served on HU? Probably not, but we can dream.