Erasure is different than censorship, and I think you’re intelligent enough to know that. I took that AP history class, and it was super biased against the workers, so that’s kind of a joke to reference.
Also, if we’re talking about a country with a seventh grade average reading level, we’re mostly talking about people who have never taken an AP fucking US history class.
Choosing the September date is part and parcel to why more people don’t know about it, because it’s not generally part of the public consciousness or conversation. That’s called erasure, not censorship.