Plan builder question for a 100mi gravel race

I have a 100mi gravel race in three weeks that I recently added to my calendar. Plan builder did its thing and gave me entirely VO2 Max and Anaerobic workouts between now and then.

I’m curious as to why: I had expected to see only threshold and sweet spot given the length of the event. Is it that the aerobic hay is in the barn so to speak, and there’s not enough time to make more meaningful aerobic gains before the race? Or does plan builder treat a 6hr gravel race as similar to a road race, complete with attacks and covering moves?

I guess now that I type this out I know the answer: I’m in specialty phase. I’m just kind of surprised that specialty phase for a long gravel race is so focused on short power (I’ve replaced the on/off VO2 max workouts with longer interval VO2 max stuff, and haven’t done any of the anaerobics yet: considering changing them to threshold).