Stretched-period échelle diagram of KIC 3216736, the only RGB star in our sample showing buoyancy glitches. The spectrum is simple, since only m = 0 dipole mixed modes are present, but shows a large-period modulation instead of the expected vertical alignment. Modes plotted in light blue are pressure dominated; extra peaks that do not follow the global trend are either ℓ = 3 modes or ℓ = 2 mixed modes. Red figures indicate the radial orders of the radial modes. For clarity, the power spectrum density is also plotted twice, top to tail.