If it wasn't a planned cycle I might cut my calories the next day by 100-200 but nothing more drastic than that. I agree that cutting drastically will only serve to start a bad binge/restrict cycle.
Not really. I'd try extra hard to be good, but I wouldn't drastically slice my calories. As people have said, I'd skip the treats I often have, and/or put in some extra cardio time, but really, it is a new day and a clean slate.