I still think you should just go to a 39 or 39x25 or else just take your road bike. Also, take your split times at the tops and bottoms of the hills. It's a short course and I bet almost all of your time is climbing, so why do you even need a TT bike? If it was me I would consider taking a lightweight road bike and maybe even go with a compact double (say like 36/50), and 11x23 or 11x21 cassette. But like you say I don't know the course.

Actually come to think of it I'm still confused about the sizes of these hills. When you say "200 foot 10% hill" I'm assuming you mean 200 vertical feet?