This can be achieved by setting the cue out point of the bed to be the point where you want the dry news recording to come in, and also set the "No Fade" flag on the bed. This means when the cue out point on the bed is hit, the next track will play (the news) and the bed will continue to play and not fade down.
* Set the cue out point of the bed track to be the point at which the news recording should be played
* Set the No Fade flag on the bed track
* Schedule items to be Bed, followed by News
* When automation plays, the bed will play and when the cue out point is hit the News item will play over the remainder of the Bed item.