Didn't PPG change the paint code for Curious Yellow to some horrible off yellow state green machinery colour some years back. Seems I read here recently of someone getting them to reformulate the colour back to the original and giving said owner enough of the reformatted paint for a complete repaint when the paint they had sold him made his car that off yellow green instead of real Curious Yellow. Found just enough original paint somewhere on his car for a sample to get the colour right the second go round.