I've been calling about twice a week myself asking when the rates will be out. The last CM mentioned that April 9th might be the likely date. Who knows if this is true, since other CMs have either declined to speculate or have given dates that have already passed. However, maybe there's some truth to this since the current AP rates expire on that very date.
My theory is that they're waiting because they want to see how the new lower rates that they're offering to the general public go over, but who knows!!