Interesting article from Taiwan's INDSR think tank on PLA airborne refueling capabilities relying mainly on Hong Kong's pro-Beijing Ta Kung Pao newspaper. According to it, the PLAAF have 3 IL-78 which have a max takeoff weight of 210 tons, carrying at max 105 tons of fuel. The Y-20U reportedly has a max takeoff weight of 220 tons, carrying at max 100 tons of fuel. The more numerous HY-6 tanker has a max takeoff weight of 79 tons, carrying at max only 18 tons of fuel.
Report (in Chinese):
Report (in Chinese):