My only goal is to complete and try to be on the course for as long as possible.
If this is your goal then I would forget about looking at very structured training plans and concentrate on long rides, preferably consecutive long rides at weekends. Find a pace that you are comfortable with and one that you think you can keep going for hours on end.
Conditions at the Mayhem and SITS can get, erm, wet and muddy, so experiencing wet, muddy conditions on your long rides can be beneficial, as is just getting out there when the weather is rubbish and other people are tucked up inside. Doing this will pay dividends to your mental ability to keep going through all weather during the event, far more than a few hours of structured training.
I now follow structured training plans for 12 and 24 soloing as I want to be in with a chance of winning or at least podiuming (of which I've achieved for 12 and 24h solos). Personally, to just finish, you just need to ride a lot and have the right mental attitude.
Also, bike setup is extremely important, set it up as you want it as early as possible and stick with it! Don't go changing parts, tyres, angles etc a week or even a month before the event. What may seem like little niggles during a 2 hour ride for example can be the difference between you finishing or quitting a 24 hour solo.
If you do fancy the structured training route though, then you can't go far wrong with the Chris Eatough plans, he is after all, one of the best. It's mostly what I follow, but with a lot of tweaks as to what works for me.
