There is no self service way to remove it. Most of the time, the segment goes away when you do fly the first flight, but I have had it get stuck and cause all kinds of confusion. I'd wait for twitter.
AA cancelled the first leg of DCA-LGA-IAH 2 weeks ago and rebooked me on the UA IAD-IAH nonstop. Unfortunately, they had IAD-IAH on UA and LGA-IAH on my ticket resulting in a spectacular mess on the UA side.