I acknowledge that Internet is a wonderful way of communication and thanks to it that we can learn very rapidly any "news" about anything.
But there is a sideback: if all collectors would know that EOH Blue Plate Number were hanging around at the time when they appeared in circulation, almost everybody would hanged on it and there would be much less rare and the value would be lower and maybe lower that the EOH Yellow.
I mean that's precisely the very fact that very few people had recognized that there was a change on a almost microscopic detail at the time when they would catch some in circulation, which had created the rarity. And the few notes in UNC grade were the few lucky which had kept one just for their collection by pure luck and realized only later that they had a rarity.
If everybody know about a rarity, the thing will be much more searched and will be much less rarer.
However, the recent history had told us that even the knowledge is not sufficient, with the so-called "lost prefixes", whereas much more persons had know about, but were unable to get the rarer prefixes. And almost every collector missed at least one or two prefixes... :-/.