BUG: getDisplayProperties returning incorrect HDR value

I've noticed on my Roku Ultra (4640X, 8.0.1 build 4042-29), when set to "4K HDR 30Hz TV" the suggested hdr10 property returns false. When set to 60Hz, it returns true. 

Function canPlayHDR() as Boolean
  dev_info = createObject("roDeviceInfo")
  return dev_info.getDisplayProperties().hdr10
End Function

I believe both these modes should return true. Am I missing something here?