Tom Van Horebeek:

What are the units of the number that is filled in as the upperBound in the boundVariableRateOfChange in the constraints of rtcObjectiveConfig?

Is this value the maximum difference between two consecutive values of the variable (regardless the length of the timestep)? Or is this upperband the the maximum difference of the variable per timeunit (so the maximum between two consecutive values is the product of this upperbound and the length of the timestep)?

This feature is not unit-aware. Make sure you use consistent units for the variable and its bounds.

The rate-of-change is the difference of two consecutive values per time step.