I've only contemplated a HIM;
I've seen one 10 wk training plan where you have to enter with

a) being able to do an Oly without injury (wouldn't apply to me yet as I was out of commission for 3-4 days after)
b) being able to run 20K. You'll definitely have to work on that (and I would, too)
c) having "decent" (sic) base endurance

But it's early in the year and you can start from here.
Do you do hill clilmbing for strength? might be better than the Velodrome, I don't know. You can simulate that on the spin bike too.