Optical light curves (left) and periodograms (right) for the 2021 outburst, using the same colour and line codes than Fig. 5, from top (#1) to bottom (#7). We note that epochs #1 and #7 do not show significant peaks in the LSPs. When the favoured DRP does not correspond to the peak with the highest power (see Sect. 3.3.1), the last one is indicated with a vertical dashed line (#2, #5 and #6). Epoch #7 is not averaged into 20 s bins, as the exposure time was 15 s.