In reply to edordead:
It's certainly not outside the realms of fantasy, although I do think you probably might have picked a tough race for a first ultra. One of my running friends did their June race last year and found it brutal, and he's a good runner. The trouble with the coastal path is that there isn't really anywhere to get into a good rhythm, it's always steep up and down and a lot of steps.
That besides, you need to get used to time on your feet, extend those long runs at the weekend to several hours, don't worry to much about distance at this stage, just get used to eating whilst on the move and sorting out issues such as clothing that rubs. Get used to running with a pack. May is still some time away and I ran my first ultra at the end of May this year, having had an injury break from the end of Oct last year upto the end of Feb. I ran a hilly half in March, then started with good hilly offroad runs working upto 25 miles before the race. I did have the advantage of plenty of other races upto marathon distance under my belt though, so knew how to pace myself.
After my May ultra, which was the MCN Brecon 42 miler, I just did lots of shorter races for a while, then 2 offroad marathons over the summer with the MCN Black Mountains race in Sept as my objective. However, I decided at the last minute to enter the Cotswold Way 102 at the end of Sept, so the MCN became my last training run for that. I finished the 102 well, so even though I never trained for a 100 miler, my head must have been in the right place, and this is most of the battle.
So, I would get some races done between now and May, maybe a couple of offroad marathons, practice eating, getting your pace so that you are not breathing hard and teach your body to burn fat reserves rather than glycogen reserves.
Shorter, faster runs are very useful too, they make the difference when you have to push a little harder up a hill. Races are good for this as they always make you push harder than you would in training. I've never followed any training plan, I just train by how I feel.
The ultra scene is super friendly and you will pick up lots of tips along the way, so even if your first race doesn't go strictly to plan (mine didn't!), you will learn loads for the next one. Good luck!