Bad luck, Chris.
You' ll have to wait another four years and join Audax Australia (or for other readers, whatever randonneur organisation is in your country). Then you will have to ride organised randonnees of 200km in 13.5 hours, 300km in 20 hours, 400km in 30 hours and 600km in 40 hours in the period November to May in the year of the event. The time limits are elapsed, so any eat, drink, sleep and control time off the bike is included. You'd probably enjoy the challenge judging by the distances you ride.
Organisers of these events take account of all sorts of things, including rider safety, checkpoints, the challenges of terrain, careful documentation of routes, and food/drink suitable for cyclists on supported randonnees. But basically, the rider is there to support themselves to achieve the challenge. For example, no support vehicles are allowed on course, and only at certain checkpoints, if at all. On-road repairs can only be sustained by the rider, another event rider or at a bike shop (!?). Apart from that, it can get quite lonely out there. Body management is a critical issue. Even more so is mind management.
Paris-Brest-Paris is an international 1200km bike ride with a time limit of 90 hours conducted from 18 August 2003. The largest group departs Paris at 10.00pm. The ride is held every 4 years. Anyone completing the distances above, whether as qualifiers or not, becomes a Super Randonneur. The information is entered into a register held only in Paris, and for each successful ride an individual completes, a brevet or certificate (a very small one!) is issued with a unique number on it. A small plaque is given to successful PBP participants.
Randonneuring is quite an exclusive club -- even as can be judged on this list. This year the PBP entry limit is 4000 (up from the usual 3,500), with a fairly large American contingent, along with some 80 Australians, and entries from something like 15 other countries. The French make up the majority of entrants. The French public love the event almost as much as the TdF, and get out along the route with food, drinks and even offers of beds for the participants. The most famous words are: "Bon Courage!" as riders pass by. This support, evidently, is what gets many riders to the finish.
Super Randonneurs who complete PBP and/or its North American sister event, Boston-Montreal-Boston, are truly considered super-cyclists in ordinary cycling circles.
I'd put my faith in the knowledge of an experienced randonneur such as Machka anytime, as they usually have experimented or had experience with a vast number of things to do with riding -- sizing, bike type, seats, handlebars, fuel, rehydration, tyres, etc, etc -- and have suffered the consequences of failure or close to it (which can be unpleasant, serious and long-lasting).