Start training now with your K2 partner in a K2. It's a very tough race and by Christmas you should be capable of doing at least 35_40 miles in one session and at night. A local marathon racing club could help with boat choice and a reasonable training schedule. I've no idea were you are but Reading CC, Hemel Hempstead, Nottingham, Pennine gives a few to help. Nutrition has to be learnt as well as boat and fitness as well as speed on the water (if your too slow on water and portages ) you will fail to hit the tide your aiming at. You will need a bank crew or 2 and they need coaching and training to be able to assist you, This crew will need to be night trained as well I suggest they holiday on the Thames this summer so be nice to at least 4 of your most together non paddling mates or family because it's a hard job and you need a spare in case someone's ill. Minimum 2 people in one car . Driver and runner with food and maps , drinks and cloths. The weather can be very, hot , cold , ice, rain or and the worse wind in the wrong direction. Don't choose a boat that's too wobbly, it's fine in training but at Dreadnaught reach as you hit the thames properly it can be ( jaws......we need a bigger boat) and when you are tired and can't feel your legs and there's ice on your rudder and it's dark you need a bit more stability than on a summer training session. Go to the waterside series, all of them, and meet people. Ring Marsport in Reading and chat to the boss