A lot of great points have been raised. Haven’t looked in detail on your calendar, excuse me if the answer is there.
Just to offer a different perspective. I travel often for work for a week or two without a bike. I should be fresh when I come back, but I have found that I’m actually detraining in these weeks. Enough, such that it is measurable.
Could you be detraining? If you have 1/3 less time in intensity zones than before, it would not be surprising to me that you loose something
Looking at that, you have been ramping up TSS quite a bit from February, probably due to longer outdoor rides. You might just be carrying fatigue.
That’s really interesting. I didn’t know that feature existed, thanks!
Here is % of fitness. Definitely a few more “high risk” times now:
Yeah it’s worth considering isnt it?! Despite still doing a significant number of hours on the bike, my time in some of the higher zones will definitely be a bit lower as a result of dropping a TR workout every week.
I think, after some rest, i will go back to 3 workouts per week. Historically its worked well for me
Never change a running system 
Yeah that’s a lot of constant load into high risk so you’re probably carrying some residual fatigue and the body doesn’t want to go as hard. Looks like you’re on your way to some fresh zone time though so hopefully that will give you some energy to get back at it in a few days or so. You can certainly do some low intensity spinning in the mean time to not go all the way into the transition zone.
For what it’s worth the dips into high risk aren’t too deep, so dropping a small amount of TSS may keep you in that optimal zone and allow you to keep doing a lot of your rides without over doing it.
Aside from the arbitrary color-coding, I don’t really see any difference??
Bingo. That’s all that changed. The only thing that is different are the “Form Zones” (Transition, Fresh, Grey, Optimal and High Risk). The data points for all the lines – ATL, CTL and FSB – haven’t changed, but how it buckets them has.
Arbitrary or not, the percent of fitness version tracks with how I actually feel compared to the absolute value one. Because the correlation does exist for me, I find it useful to check in on throughout a season here and there (usually at the end of a training block). Figured OP may benefit from seeing if it tracks/correlates with his feelings as well, and it appears that would be the case.
You could just change the cut-points of the absolute scale, and arrive at the same place.
True. But I don’t know how to do that and I don’t really care to learn how. 
Thankyou for the helpful tips 
When you do such a small number of hours on the bike, i wouldn’t rely on the high risk ratings.
Also - you just dropped your training by a 1/3 and surprised it’s got harder…If you want to be any good at endurance sports, it takes volume and intensity in the right structure.
Thanks. What number of hours would be enough for you to no longer consider small?
I didn’t drop my training by 1/3, I dropped 1/3 of my high intensity sessions. And i failed a workout in the first week of adopting this strategy, which is a rather short timeframe for my lack of training to play such a large part in my performance I think?
What volume, intensity and structure would you recommend?
I’m actually scheduled for a recovery week next week anyway. Curious for your thoughts on the following options to progress:
I’d ride the recovery week and gauge how I was feeling by the end of it. If I felt like I needed more time, I’d take time off the bike and continue to monitor my motivation and fatigue. It would be a bit of a moving target.
It looks like you’re getting into that fresh zone on the graph. For me, it doesn’t take a lot of time there before I start feeling like I want to get back at it. By the end of a recovery week, I’m often just as eager to get back into the workouts as I was eager to have the rest week in the first place.
Hell, maybe you will feel more eager to get at it quicker/sooner than you expect. If that’s the case, I’d give it one extra day (much like @ambermalika has said she does) and get back at it.
FWIW I really hope it brings some life back into your legs! It’s such an awful experience to feel flat and unable to push the pedals the way you know you should be able to.
Thanks for the advice, really appreciate it.
Only trouble is that I want to ride now. Im super motivated, feel great and keen to push on. Im not aware of the fatigue often until mid way through the workout!
Obviously im not very good at doing things by feel, which is why the intervals.icu metrics are nice to have as it gives me some measurable data to base my choices on.
I guess I’ll take this next week either super easy or off entirely and then decide whats best to do. It will be a useful experiment whichever choice i make
Yeah, I’d say regardless of what you do, take some notes so you have some record to look back on in the event you run into a similar experience in the future. If it works, you’ve got a new tool in the belt. If it doesn’t, you’ll know to experiment with a different tool next time. It’s a win-win when you frame it that way because you learn something new either way!
Hard to say, but you definitely need to be doing a lot more than you are now before i’d look at that metric. One big week, and it all goes red.
I personally thing your FTP is just set too high. All the older workouts were much easier than what you’ve been doing recently. I’d just drop ftp a few % until these workouts are manageable. Vo2 and over unders are also quite mental rather than physical.
Don’t over think it, if you’re failing workouts, adjust FTP see if that helps and move on.
