Unfortunately there is nothing anyone can do about how the price is completely different on Chinese exchanges compared to US or UK based exchanges. The rumours directly affect the customer's balances on the exchanges which means that a lot of people are panic selling.

I think this should stop soon, and the price back to normal as either Chinese government does ban exchanges or they don't. Right now it's speculation.

It is impossible to take advantage through arbitrage as there is a limit on how much foreign currencies one can exchange a year in china.