In late July I was making about 20% more power at VT2 (FTP) and 10% more at VT1 than I currently make.
I did Paris Brest Paris in the middle of August and injured my rotator cuff subsequently. I cut back on training
My non-brevet weekly volume went from 300-400 miles to 120-150 miles with a bit less intervals due to pain.
Although my data is not from an off season, I am nonetheless shell shocked at how much power I have lost.