Thanks.

XIAMEN Air is the airline but the final destination is Fuzhou on the coast in southestern China. He was told he would have to go through customs in Shanghai and then re-check to Fuzhou. That's why the 7 hour layover comes into play. How far in advance can he re-check the bags?

His flights are B Economy and K Economy. No Y.

20kg is 44 pounds. He wants to bring two 50 pound suitcases! (They are full of stuff for his presentations). That's why he wants to know the fees.