Example light curves illustrating the four different subgroups among our sample stars: (i) g and r data are in anti-phase (upper left panel), (ii) the amplitude in r is larger than in g (upper right panel), (iii) the light curves in g and r are not consistent (lower left panel), and (iv) eclipses with possible additional ACV variability (lower right panel). Orange, red, and green symbols correspond to i, r, and g band data, respectively.