China is scrambling to contain a stock-market rout only two years after the previous rescue. Beijing is dusting off the market-support playbook it deployed in 2024. The People’s Bank of China is providing low-cost funding for corporate share buybacks and liquidity for institutional investors. The shadowy “national team” appears to have stepped up its operations, while regulators are again resorting to window guidance — informally instructing institutional investors and brokerages not to.