I have said many times that a good red herring can't be just a false trail. It must not only must go someplace interesting, it has to lead to quality information. It has to fill out the picture in which the story takes place.
That fact just smacked me in the face once more, as I struggled to get a little more information into one scene, and I realized I need a red herring to flesh the dang thing out properly. So I sat down and started brainstorming, and I came up with several tonight, and tied them together, and to the main story. And I think it will only add a scene here or there - but in places where the story felt thin anyway. I don't have to cast any new characters or create new geography. I just have to make more use of what I've got. (This will also flesh out the field of suspects.)
Which means, of course, that I have once again moved the goal posts in terms of how much I need to do to get this thing finished. I'm still determined to do it by October 20. But some of the stuff that was a pain to write should be more pleasant now. That should help.