I'll be interested in your experience of this as a pump user, I'm hoping to get one myself.
With regards to training, time on the bike is going to be key, you need to build yourself up to be able to spend 4-5 hours on the bike comfortably, maybe 4 stints of 90 mins each over a day.
Do you need to do a set mileage each day, or set duration? You need to be able to do at least one day at that really with no adverse effects the next day. I'd be looking to find an average speed I could do and still feel I could do more in one day. TRaining for speed is not going to help you, but as the nights draw out I'd be looking to get an hour on the bike several evenings a week and a long ride on Sundays and/or Sundays.
As for the diabetes management. my strategy on MDI for a long run/ride in the morning is
1) basal dose down from 3.5 to 1 unit (levemir)
2) Bolus down to 1 unit, just to keep the blood sugar moving into the muscles
3) test regularly - I've pushe it out to once every 45 mins on the bike, once every 5km running, but started at shorter intervals until I had an idea how I'd react
4) carbs, starting point would be about 60g per hour, mix of medium and high GI as you want to encourage fat burning over that distance - you can't take carbs in at the rate you expend them, buut need tome to keep the fat metabolism working as well, Eat about every 20-30 mins in small amounts tailored to your BG readings.
I've been thinking about how i would do this if I were on a pump and I think the right way would be to just turn the basal right down to the minimum and have no bolus while riding. You'll also need to reduce the bolus and basal in the evenings after each day as you will be eating to replenish glycogen and need to avoid hypos as the muscles and liver restock.
Taking my approach, my last long run went like this
Pre Breakfast 6.4, +1hour 14.3; 1U bolus, 1 U basal, 45g carbs for breakfast
5km 5.2, 20g carbs; - See how quickly it comes down, even on minimum insulin
10km 5.9, 20g carbs;
15km 5.8, 30g carbs;
21km 7.0, 25g carbs
Total 45+95 = 140g carbs;
Post run readings
+30min 9.3;
+70min 9.3
Pre lunch 7.0, 60g, 4x0.75=3U; - see how it's coem back down again, and note reduced bolus for lunch
+1hr, 3.8, 30g; - walking to the park with the kids, hypo averted, this is the delayed hypo effect
+2h 40, 4.6
Pope me a PM if you need any more info, I've got similar data from long rides, but the principle is the same either way