It's happening, the Michael Matthews Foundation team started in Oceanside, California on Saturday, and plan to cycle 3,000 miles, 24 hours a day to Susan G. Campbell Park, City Dock, Annapolis, Maryland between June 20 and 24.
In case you want to eyeball Pippa, Kate's sister, who's on the Matthews team, here is a
61 page pdf with the whole route. Very complete, even moon phases, odd obstacles, and parade sections.