Yeah! You’ve been crushing it! Most everything was in spec from this period you were talking about. The only struggles I’m seeing are coming from Threshold workouts, but that’s minimal. Overall things were going great!
When I run the admin tool to find out what your FTP would have been with the new version of AI FTP Detection on Jan 10 (the date you were given 316 by the old version), it shows 309, so I’d use that as the point of reference.
Crucial to point out your FTP did NOT drop from 316 to 309. It was already at 309.
The first workout you were prescribed after the switch to using the new version of AI FTP Detection was on the easier side. That said, and judging by the comment, I’m not sure if you were trying to sway the model with the survey response, but you rated this one Easy even though you hit HR of 177, which is 5bpm higher than what you have hit in other Sweet Spot workouts recently that you rated as Very Hard. I don’t know for sure, but I think this was a bit of an anomaly for the model to deal with, and possibly affected your next Threshold workout more than it would have if the survey was not answered as Easy. Of course, I could be wrong in my assessment that this was not Easy, but in other situations where you’ve marked workouts as Easy you are typically between 140-160HR, and Moderate is typically 150-160HR.
After this it looks like your next VO2 Max workout was appropriately difficult.
Then for your next VO2 Max workout, it was 55% likely to be Very Hard and 40% likely to be Hard. You rated it Hard, which isn’t far out of spec, but you hit 182HR in this one and had tons of 6 week PRs, so this one looked like it was pushing your limits well. Whether “Hard” accurately reflected what you felt is something I can’t know, but signs would point to this one being Very Hard, but still not far out of spec if it’s rated “Hard”.
Your next Threshold workout was 65% likely to be Hard and 25% likely to be Very Hard. It’s an objectively harder workout than what you got the week before and you reached 179HR. If we look at the average power you did for those intervals, it was only 2w off of your 6 week PR, so that info, combined with your HR data would suggest this was harder than “Moderate”. Again, I’m not sure if you were trying to sway the model here or if it did indeed feel moderate, but the data makes a “Moderate” rating a bit puzzling.
After that you had a recovery week and then you had Blue Top.
You ended this workout early and hit an HR of 182, and based on what you’ve said here, I assume this was due to intensity, but that you didn’t mark that down as the reason. Instead you marked “Other” as the reason and stated “Your shitty fucking AI.” as the reason 
. It would be super helpful if you could mark the reason why you had to end this one early. 
Looking at the prescribed power on this workout, it was only a handful of watts higher than what you had done for 2.5-3.5min for the last 6 weeks, and when we look at that same duration compared to your all-time power, it was 128-148w lower.
TR AI doesn’t use Workout Levels to pick your workouts, so if we view them from this lens, it gets confusing. It’s better to look at the power you’re doing during the sets/intervals and see how that compares to what you’ve done recently.
When you do this for all of the VO2 Max and Threshold workouts you’ve been prescribed since starting to use the new version of AI FTP Detection, you can see that there’s actually a pretty linear progression.
That first workout after starting to use it was a big conservative, but that’s the only outlier I’m seeing when looking at the Power Records charts.
But above all, and this is super important, TrainerRoad AI has been picking your workouts for over six months now behind the scenes. So when you perceived things were going great, that was all due to TrainerRoad AI and that hasn’t changed.
The only “change” is that you started using the new version of AI FTP Detection. It didn’t lower your FTP, you just started measuring FTP with a different scale that is proven to deliver better training outcomes.
In terms of the workout prescriptions after that point, other than one workout being a bit on the easy side (and predicted to be so), your training looks pretty well locked in based on the Power Records charts.
My suggestion would be to stick with it through this next block and to fill out your surveys objectively based on what it asks of “How did that effort feel?”. This will always lead to better results.