I returned to the North Inch at Perth today to the scene of the 24 hour race on 13 September. I wanted to see if I could have a run of at least 2 hours, at 24 hour race pace, and finish because I wanted to rather than my knee was forcing me to. And guess what? It happened just as I had hoped! Allybea came up with my and gave me water after every lap (2.38 km/1.48 m). I covered 4 laps in the first hour, 4 in the second, then an extra 2 in the next half hour for good measure. 10 laps/approx 15 miles in 2 and a half hours. And, even better, no problems with my knee.
So the 24 hour race is still possible. If I can get 2 decent weeks training and have no adverse effects, then I'll do it. Even though I felt I was going really slowly today, I was still averaging 6 miles an hour, a lot faster than the pace I would expect to average over a full day. That is encouraging - it means I would be able to build in a reasonable stop every couple of hours, and still be covering a fair amount of distance.