Hong Kong Exchanges and Clearing chief Charles Li Xiaojia has no idea when the scheme to directly link the Hong Kong and Shanghai stock markets will eventually begin operations, after the so-called "through train" missed its anticipated arrival date today. Li told the South China Morning Post that all the technical and regulatory work on the Shanghai-Hong Kong Stock Connect scheme was complete and declined to speculate on the reason for the delay. "Some smart people up there have to make the decision," Li said, referring to officials in Beijing, when asked who had the final say on when the 550 billion yuan scheme (HK$694 billion) would eventually get going. Li refused to be drawn on whether the pro-democracy Occupy Central protests had played a part in the delay. "I do not know," he said when asked, adding quickly that the scheme's complexity and recent volatility in global markets could also explain the delay. Some brokers believe the delay is Beijing's punishment for the month-long Occupy protests. Others dismiss the theory, arguing that the mainland needs to attract huge sums of foreign capital to domestic financial markets as it pushes ahead with a structural economic reform programme. The uncertainty has left institutional investors increasingly frustrated at the opaque decision-making process. "We would like to see Beijing announce all rules and regulations in detail at least several weeks before the scheme is kicked off," said Bruno Lee Kam-wing, chairman of the Hong Kong Investment Funds Association. Changes to fund management mandates, legal disclosures and client consent would be impossible to secure before full details of the scheme's trading rules - including those for settlement where a risk of insider trading could exist - were made public. None are expected before a start date is confirmed. Premier Li Keqiang caught regulators and markets by surprise in April when he said at a business forum in Hainan that the "through train" - mooted since 2007 - would be ready to go in six months. Officials have been silent on a start date since, though Hong Kong government sources had previously told the Post that the city's top financial officials had been told to keep October 27 clear for a possible trip to Shanghai, which had fuelled expectations of a launch by today.