Quick work, if they did so since the preprint was posted six days ago, of which two were a weekend! My version of ChatGPT claims to be the 3rd August version, which gave them one day to respond unless they were somehow targeting some sneak peek pre-preprint.
A whole four working days to adjust the model in between preprint release and the version of ChatGPT I'm using, then! Do you think that's plausible? I certainly don't.