apparently 923 and 924 are supported way earlier
it's REALLY confusing apparently because yes those clients DO handle those codes, but HOW?
makes me want to throw out the error code tables because it seems like different clients implement them in different ways with no established rule, especially those two because only 924 doesn't appear in plain text in the main binary until P7, but it absolutely exists before then?
And for 923... I don't even know. It's not in the main binary (at all). Let alone in later versions.