I see _writeCommand(0x10) here here which looks like it might be the command for selecting the black channel. Is that right?
Where can one find a list of these commands (some of which you have helpfully commented)?
I see also the data is defaulted to 0xFF here, so that's what I'd need to change.
My skillset is better suited to rearrange the hosted data though - I think I'll be faster at that. I'll leave these links for posterity though and I appreciate the fast response above, thanks.