Arrows next to Erg Mode button on Companion App

When doing a Free Ride block within a workout, I noticed that the Erg Mode toggle button has arrows on it. If I hit the middle of the button, I get switched to resistance mode as expected, but if I hit the arrows, the erg mode bar graph switches to a line graph but the button still reads “Erg Mode On”. How does this differ from the FTP bias buttons on the right side of the app?

That line graph is incline mode. if you tap the arrows on the incline button it will change the resistance of the trainer.

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