Look at the founding year of Dye!Dye!Dye!. It is 1802. How it is possible if there is only 451 year of Fourth Epoch? Does it refer to the Third Epoch? Or maybe it is an Earthling Intrusion in Aerwiar?
However, this date's presence makes the whole scene (accesible here: https://www.youtube.com/watch?v=qCqW8OzqTfA) look even more dangerous and intimidating, giving an impression of something being... wrong, so I think this error is legitimated in some way.
What if there's universe travelers and they brought that poster over?