So how is it "White Label" if it is black??

This is the ruleWhite Label - Only use this tag to indicate when the center labels on a vinyl release are without mechanically applied print on either side. Additional marks with a rubber stamp, small printed sticker, or handwritten on an otherwise blank (but not necessarily white) label would still generally be considered a White Label release. White label releases of the same record may be entered as separate releases if one version has been stamped while another has been labeled with a sticker.

Pre release demo copies I think in white with some signatures?