I was thinking it would happen after the restricted are free-trading too... BUT... I have also been suspicious that the whole preferred/restricted share thing may be have been some sort of deal with shorts that were out there... "Convert and cover your shares or you will get burned." (I'm convinced there were at least 4-5 billion shares outstanding about the time of the preferred dividend when more requests for the dividend came in than the O/S allowed.) In this case, a run could happen before the April 30 date.
DD
Whatever I say is my opinion -- and I don't know anything, so don't listen to me.