The China zone gets about 100,000 NTP requests per second (or maybe more, but that order of magnitude). It's basically impossible to join it without getting tens of thousands of queries per second.
To "bootstrap" it I'd like to add 25-30 servers (or more) at once (from anywhere in the world).
I'm planning to make the software do this automatically for underserved zones, but similarly to what was once done for the tr zone, I'd like to do it for cn.
So ... if you are running a server in the pool and wiling to help out, please reply to this topic or send me a private message or email. I'll add all the IPs at once when I have at least 25 IPv4 servers.