Color-magnitude and color-color diagrams with the slopes for the stars presenting a linear variation. Red lines show disk-bearing stars, and blue lines show stars without discs. The length of each line segment reflects the amplitude of the variability. The dark red arrows show the median interstellar extinction toward CygOB2, and the gray lines show as reference of unreddened normal photosphere colors, an empiric isochrone from Kraus & Hillenbrand (2007).