Have you thought about buying a powercharger and charge your FR 410 on the run? I use this method with my Timex Runtrainer 2. It does not work with all watches though, as some resets or the screen blacks out.
Sorry if I am slightly off topic or if this has been covered before (it´s a long thread). I am thinking about using the Comrades Finishers Programme from the race´s official site for another ultra I´m gonna do in the end of july.
As the last run in the fourth week in april the programme says "Rest or 50-55 km long run". Is this a typing error? Sounds a bit weird that you should either rest completely or run 50-55 km (app. 31-34 miles). Maybe it shall be 50-55 minutes?