Friday 4/3 had ORD-DCA delayed for over 2 hours for mechanical. Called and was told the same story ,that a new memo forbade them from getting me a spot on a later flight unless I wanted to give up my seat on the one. I was told to call back in a hurry if they cancelled the flight, since it was a heavily booked holiday weekend. That plane ended up not going, but they moved us to another plane, which then had a new set of mechanicals, and we boarded, had to get off, and eventually reboarded and took off.