300 rule

If the 300 rule isn't true, then why would 4 sororities cancel their COB events and send numerous girls emails apologizing about the new rule and? Why in the world would they all conjure up a rumor and lie to us all? PHA wouldn't let them do it, so there has to be some truth to it. I don't like it because I'm informally rushing, but I just don't know why they would lie...