There is an older thread which mentions this. I can’t find it but will continue to look.
Those Progression workouts appear in the FTP building block (once a week) and I’ve found it a tough block to get through. So long as I stay fresh for those particular sessions I’ve managed them. In the past I’ve been stupid and tried to add some running in to the block. Result: massive blow up on the Progressions.
Edit: Found it I think (similar is mentioned elsewhere also):
FTP Progressions
I was about to tag @Heretic as I know they have opined on these workouts a lot, but then I saw they were writing a reply so…incoming! 