sub Zwift races for workouts for SST, threshold and V02. I do look at how many intervals I have and interval time in SST etc and at least do that time plus more. Just without the rests. So I stick to my plan as much as possible.
So on Monday I have Monadnock +5 scheduled which is 6x4 min. VO2 Max intervals at 115% FTP. So that’s 24 min. at 115% FTP. So I would just make sure to do those intervals at some point during the race if I’m following your concept?