EWOCS light curves and periodogram of star A. Top panel: broad-band raw light curve produced by the dmextract tool. Second panel: broad-band probability-weighted light curve produced by the glvary tool. Third panel: resulting LS periodogram and the FAP levels of 0.01, 0.1, and 1% are marked with the dashed, solid, and dotted horizontal lines. A clear peak at about 81 days is detected. Bottom panel: Same as third panel, with the normalised window function overlaid on the periodogram.