Spelling of Kilometres on ArcGIS Pro scale bar?

Being in Australia I like to see the spelling of "Kilometres" used on my maps in preference to "Kilometers".

In ArcGIS Pro 1.0 I have not been able to find an option to change the text used for units and so my scale bar looks as below.

I have looked at the Element Properties for the Scale Bar and was hoping that setting Region and language to English (Australian) might do it but it did not.

Does anyone know how to set a spelling of "Kilometres" on an ArcGIS Pro scale bar?