Motion blur with different transform/planar transform nodes

I have a shot that I tracked with two different planar trackers, because there was a section in the middle of the footage that I needed to do by hand with a transform node. So the movement from the track is currently one planar transform for the beginning of the shot, one regular transform with manual keyframes in the middle, and then another planar transform at the end. Since motion blur is done within the nodes containing the movement, how can I add motion blur to movement over the entire shot? Adding motion blur to each of those nodes leaves the transition frame without motion blur, since the first frame of the new node hasn't moved from the previous frame.