Seems like more is going on behind the hood in AT than the Career page actually displays. My Threshold progression level was at a 5.3, but as I entered a Sweet Spot Base II training block, I was dreading the next threshold workout, which had was an over-under threshold workout somewhere right around 5.3. Much to my surprise and delight, just as loaded up the TR app to do the workout, AT suggested adaptations for all of my upcoming over-under threshold workouts for the next 4 or 5 weeks, bumping my workout down to a 4.2 that still felt very hard. Can someone else confirm that AT is tracking different progression levels within each “Zone?” Seems like AT has a over-under progression level of 4.2 for me and a regular old-fashioned threshold progression level of 5.3. I wonder also if AT will bump my progression level back up when I end SS Base II and enter my build phase.
I don’t think that AT tracks different progression levels for each “sub zone” directly as you describe but I think that your plan does adapt future workouts differently depending on what day of the week it is.
i.e. if you you have threashold workouts monday wednesday and friday and you don’t complete wednesday then the planned workout next wednesday could be adapted lower and monday and friday stay the same.
Due to how the plans are structured this probably does have the same effect you describe - with certain styles of workouts in the same zone being adjusted differently.
This is just guesswork based on what I’ve experienced.
I think you’re looking into it too much, even though It has adapted workouts 4 to 5 weeks down the road those workout probably won’t stay the same. It all comes down to how you grade each work out up until then, it goes week by week.