you get kick-muted, your chat refreshes. (I hope this doesnt mean that it imposes some sort of client side block that can be hacked around) any messages you try to send result in a (similar to a you dont have an internet connection or you posted too many times in a row) you're suspended do you want to retry sending the message.
after the period your chat auto refeshes again and you can post, but if I never posted in the period between the first and final refreshes I wouldnt have noticed I even got suspended