JBL,
I assume you've been in touch with places like the flying clubs at St. Just, Bodmin, Perranporth and Davidstow. I'm sure they'd like to help out.
Anyway, I appear to have got it all wrong;
When I read,
The plan is for 45 teams of people to walk the entire South West Costal path in ONE DAY, that's 633 miles!
I was apparently mistaken in thinking that some of the walk would be taking place at night. Silly me!
Penzance 21 March
Sunrise: 06:19
Sunset: 18:38
14 miles in 12 hours, that's the speed greater than 1 mph sorted.
And should anyone wish to donate;
Steve Gibbs is fundraising for Breast Cancer Care - JustGiving
Macmillan Cancer Support - Boots South West Coastal Path Challenge