South Africa Question

This might be a stupid question but I'm wondering if someone can explain how Lutzville Valley came to be considered part of the Costal Region and not part of Olifants River region.  On a map this district looks to be nested within Olifants and at least 30 miles north of the Coastal Region's border but with the WO scheme updates last year is now considered part of the latter.  I'm confused as to how this can be.  Any assistance on this topic would be greatly appreciated.  Thanks!