Bad luck Nicole. Marathon training NEVER goes smoothly does it ? Why not cut back on the mp runs and concentrate on distance ? You`ve still got 6 1/2 weeks of training time (assuming a 3 week taper) or 7 1/2 weeks with a 2 week taper. Plenty of time to get some good solid mileage under the belt. Running up and down Cornish hills sounds like hard work (esp in this heat !) but will do wonders for the strength.
Robbie there are pace groups: "There will be pacemakers in every starting block. They will be carrying balloons and wearing yellow shirts with the words PACE 3:00, 3:15, 3:30, 3:45, 4:00, 4:15 or 4:30" - from the Berlin website.