Whether they are down or not, DJI's chat is completely helpless. They provide the chat reps 5 phrases in very broken English. If you be firm with them and demand actual information they will end your chat I've learned from experience...
You can email them and it's the same. I spoke with a chat chap and he told me the same thing I expected.. no idea when my order will ship. However to calm things down he told me that 28th and 29th sep Mavics started shipping .. mine is 30sep.. so as usual I just wait it out. So yes chat is useless .