The reason why is booming gold sales.
Gold demand in China, the world’s largest producer, gained in the first half as government measures to cool the property market and falling equities spurred investment, the Shanghai Gold Exchange said July 7. Spot gold gained to a record in June as investors sought to protect their wealth amid concerns about the global economic recovery.
“China’s domestic production of gold, albeit the largest in the world, cannot satisfy its demand,” said Ellison Chu, managing director at the precious-metals desk at Standard Bank Asia Ltd. in Hong Kong. “By allowing more foreign participation and more Chinese commercial banks to import and export, China can better balance its demand and supply.”
It's interesting, given that PRC mercantilism typically favours producers. My own guess is a decision has been made to let gold be accumulated by the mainland Chinese people rather than through official forex reserves. The latter move might come later, but not without a substantial decline in prices. The PRC monetary authorities might have been waiting back in February to see if they could get a lower price than the Indian central bank: that price point makes sense as a competitiveness metric.