This message happens when recoloring a spot color with a process color in Colorist. A spot color is a custom color including Pantones. If you respond No to this message, it will apply the process color to the color chip and preserve the color as a process color in the Illustrator Swatches. If you choose yes, it will apply the process color to the color chip and it will convert the process color into a spot color in the swatches.
For further information please contact us at support@aquariodesign.com