Evolution of the filling factor distribution with respect to phase for EV Lac, for observations recorded between MJD 59385 and 59515. Solid lines show a fit of a sinusoidal with a first harmonic to the data, assuming the rotation period obtained from our GP fit (P_rot = 4.362 d, see Sect. 4). For each filling factor, the dashed line marks the median of the series of points. Similar figures obtained for DS Leo, AD Leo, EV Lac, Barnard’s star, PMJ J18482+0741, and CN Leo are presented in Figs. B.1, B.2, B.3, B.4, and B.5.