In reply to Wainers44:
I think its less important than you think. If you've done a marathon then you know carb loading is important. Less so for ultras though for two main reasons.
1. An ultra is run at a much slower pace than a marathon, so you're burning a higher percentage of your calories from body fat reserves rather than the glycogen stored in your muscles.
2. You can't possibly eat enough carbs beforehand (and store as glycogen) to fuel you through an ultra. It's a deficit sport and you'll consistently be burning more calories than you can eat so its better to eat what you can continue with for hours and hours rather than loading up on simple carbs.
Just eat what you would eat before a long training run. I always find a couple of slices of toast with honey, or some porridge is good. I normally eat a banana on the way to the start line and sip some energy drink. But don't overthink it or worry too much. Chances are you'll be nervous so stick with what you fancy and don't worry if its not much.
That said, all the ultras I've done have been 3 or 4am - so a midnight start time you're going more for a supper and eating throughout the day, than trying to get a breakfast in. Its often said that an ultra is just an eating contest with some running thrown in anyway.
Good luck - which one is it?
