Oh sorry, yeah, it probably is an array. In that case, I think the only way to modify it would be to resize it and then explicitly set the item at the last index. Alternatively, because the attribute on the PowerManagementGroup is not read-only, you could just replace the whole thing.
I do wonder if changes to that class are actually applied to the repository settings dynamically though, since that would be counter to the way most of the rest of the API works.
Currently, the Power Management settings are read-only when accessed from the API, so changing the SlaveNames in the object won’t be reflected in the database.
It would be possible to add functions to save the power management options, and to load/save the Repository Settings. Maybe we should just do that…