ZTF light curve of ZTF J0116+4417. The top panel shows the full light curve and clearly shows that the amplitude of variability changes over a timescale of years. In the bottom panels, we show the folded light curves per part of the data as indicated in the top panel. The y-scale is the same for each panel, except for the bottom-right panel, which shows a more zoomed-in view. The bottom panels show that both the amplitude and the peak-phase change slowly over time. For example, the difference in peak-phase between year 1 and year 2 is almost 0.2 in phase, and the amplitude change between panel 3 and 4 is almost a factor of 2.