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tokens: can also be seen in more detail in Fig. 9 , where we show the running median spot properties and the typical uncertainties in spot coverage versus spot temperature plots. Phase 1: a general decline of amplitudes in V and R c , while remains almost constant. During the first half, the spot temperature declines from about 5500 to 5300 K at constant spot coverage (0.3), followed by a shrinking of the spot coverage to 0.2 at constant temperature. The initial decrease of temperature occurs at a rate of about −2.2 K/d. Overall, this is a phase where spot activity declines. Phase 2: there are only minor variations in the amplitudes, with a maximum in roughly in the middle of the phase. The spot temperatures are constant (5450 K) within the uncertainties, with a weak trend of slightly increasing values at a rate of about +0.2 K/d. The spot coverage (0.2) is also constant within the uncertainty. Phase 3: there is a clear trend of decreasing amplitudes in all filters, by at least a factor of 2. As for the previous phase the spot temperatures do remain constant within the uncertainties at about 5600 K. The spot coverage decreases from 0.35 to 0.2, with a small increase towards the end of this phase. This phase contains the high cadence data (indicated as grey in Fig. 8 ). Due to the large amount of data the amplitude uncertainties are much lower, and hence also the spot temperature and coverage uncertainties. The analysis of this data with a much smaller ±15 d window is shown in the bottom left panel of Fig. 6 . The results are consistent with the results obtained for the entire light curve. They show the spot temperature decreasing from 5650 to 5500 K. At the same time, the spot coverage drops from 0.35 to 0.2. Overall, the characteristics of phase 3 are similar to phase 1, but at slightly higher spot temperatures. Phase 4: the amplitudes remain constant for a large part, but start to slowly increase towards the end. Accordingly the spot temperature (5400 K) and coverage (0.15) remain constant throughout, and only increase towards the end. The temperature increases at a rate of +2.9 K/d towards the end. We note that the duration of all phases is significantly longer than our time window of ±60 d, and they are hence unlikely to be an artefact. One possibility to interpret these phases is as lifetime of large spots or groups of spots. If that is the correct interpretation, the spot lifetime in the four phases would be >180, 230, 360, and >230 d, overall, or between half a year and one year. These values are consistent with spot lifetimes determined in the literature for active stars. For example, Giles, Collier Cameron Haywood ( 2017 ) used Kepler data to estimate spot decay time-scales between 20 and 300 d for K-stars. A fast rotating single star like V1598 Cyg would be expected to have a shorter spot lifetime, but a potential close companion and tidal coupling may extend the lifetime. As described in Section 4.1 , we find a long-term change in the