Forgive my ignorance, but what exactly stops the Yuan's value fluctuating based on market conditions? If the likes of George Soros can destabilise the GBP back in the day, what exactly keeps the Yuan stable? Does the Chinese government basically promise to indefinitely buy and sell Yuan at a fixed USD exchange rate?
Individuals can only exchange $50,000 per year and $500 per day.
So what do the wealthy hitting it large in china do?
If they aren't part of the nomenklatura or otherwise have enough pull I'd assume deposit their money in a PRC bank, stock market or venture, etc. When there are currency controls you by definition don't have much in the way of out of country options.
People's Bank of China will exchange practically unlimited amounts of Yuan to USDs for other banks in China.