I lock myself away to polish up the script bearing in mind David's comments.
I also add a new scene and re-vamp the final sequence entirely.
After I have submitted the new draft on the agreed deadline (phew!), I look around the office where I work. It's a tip. So is the rest of the house.
As I get busy with the duster and hoover, I have a quiet sense of satisfaction that everything play-wise is on schedule.