Not for a tri: training direction/help

i’m signed up for the dirty kanza 200 the first of june. next week i’ll be heading out of town and living in a hotel for about 2-1/2 weeks. i got a kickr this week, signed up with trainerroad and did my 20 min test today. i started the dk a couple years ago but didn’t finish. i can do 100 mis right now on my cross bike no prob, but working up to 200 indoors i’m not sure how to go about this. following their flowchart i’m at advanced build 1.

i have no idea if these will tell anyone anything but here are my numbers from my test:
ftp: 273
lthr: 138

i’ll prob only be able to ride every other to every third day. so…
*get into the adv build 1 program, follow that plan as best i can.
*pick a 2-3 hr workout every other ride. i can’t imagine doing more than 3 hrs on an indoor trainer. i think i can pull off 2-3, more than that…dunno.
*what do yall think.

thanks for your time.
j-