FT of the full Kepler dataset of KIC 2991276 (upper). Magnifications of the regions for the most significant peaks are shown in the panels on the lower left. The 5σ level is plotted as a line in each panel, and the Lorentzian fit for the most significant modes are shown as curves. In the lower right-hand panels, the amplitude and phase for the two main modes are plotted for consecutive 20-day chunks. For the amplitude/phase fits, the frequency was kept constant, and points with amplitudes of less than 1.5 mma were dropped.