Workouts look different in companion app to Zwift

Hi all,

This has been bugging me for a while and I can’t find an answer elsewhere on the forum. I am currently doing a 6 week FTP builder workout plan and have noticed that the plan in the companion app (on android) looks mostly the same as, but not 100% the same as how it looks during the workout in Zwift (on PC).

Often, in the companion app, it seems some intervals are grouped together and labelled “OU”. What does this mean? Optional Unit?

When I actually get to the “OU” interval during the workout, it consists of several less intense intervals than the one shown in the app.

Any ideas?