We see the message “Sorry, we were unable to connect to chat. Reconnecting in 2 seconds.” when sending chat messages.
We’re probably hitting the limit you described which is unfortunate because we want to do team-wide playtests internally on the platform. I suppose we could write our own simple chat server that fakes Twitch IRC responses for testing to avoid this but I’d prefer to test on the platform to ensure our integration is working correctly in the real environment.