Scheduled Events Periodically humans anxious about all the changes coming about hope for something solid. Something akin to when the President calls a press conference and at last explains. Something akin to when a dying man comes clean and hands his diary over to an investigative reporter. Mankind these days is dealing with general uneasiness about the millennium, which is supposed to be the end of the world or at least catastrophic, the alien presence, which they are told may or may not be true but which is constantly in the news in some manner or another, and their sense of weather pattern changes that seem only partly explained by the Greenhouse effect.
Many people are telepathic, and listen to each other when they share anxieties.
If more than one thinks something is going to happen on a particular date, it is because they are telling this to each other.