Had a thought while Zwifting this morning… checked Strava afterward and I was right!
So, when I did this ride, I actually rode FIRST in Watopia. Just a free ride. I had signed up for a TT event in Bologna, so when that rolled around I clicked and joined that event, and did my 20-minute test there.
Zwift seems to get confused when you do two different “events” in one session… for example, my Zwift Companion activity summary for the Bologna TT shows leader jerseys I won on the Watopia ride. So I thought… maybe the power curve was somehow carried over from the Watopia event too?
Viola! My 20-minute power for the Watopia event is 258w according to Strava. So that’s what happened…
Hope this helps the Zwift wizards fix a bug.