Hell no. They can leave. Some can stay but most must beat it. Once Africa starts manufacturing (which is already happening with China's investment) along with other regions, they can go back and sell to their fellow African brothers. China needs to move out the cheap manufacturing and cut off their main line. Cheap manufacturing is what bring these nigs to Guangzhou in the first place. If China wasn't trying to shove all their cheap ass products to Africa, then we wouldn't be dealing with a nigga infestation problem. Remember the made in China 2025 strategy (ADVANCED manufacturing). I've also read articles of Nigerians being deported too for drugs. Its a good thing.

Guangzhou is a Chinese city, not planet of the apes. Your preposition is ridiculous. Also the definition of permenant residence in the source you mentioned covers a stay for at least six months. Some Africans stay for a bit to get what they need and then they go back. Its not necessarily trying to stay forever.

Shanghai has a light infestation, Guangzhou has a dark one. Whites also overstay sometimes and I've heard of Mongolians trying to enter China illegally on certain occasions.