We might see a ban in the next 2-4 weeks, maybe earlier, no one knows for sure. But i assume that the experiment Bitcoin in China ends for now.
If the chinese government issues an official warning that´s almost the same in China as an outspoken ban. If the exchanges don´t close out of free will , then they will probably be forced to do it. That was the reason why they moved from China Hongkong last year, after the warning. So either they close their shop or they move to another country. Of course this would be a problem for chinese customers, as there are strict regulations about transferring money out of China.