ETV residuals fit to quadratic and cubic polynomials. These are taken from 41 secure LTTE and LTTE + DE fits. They are continuous reconstructions over a 5000 day interval (spanning the Kepler and current TESS missions) using the polynomial coefficients that were part of the fitting process. The colours are merely to help the eye separate the different curves. The three curves shown as dashed lines that go off the scale of the plot likely represent higher-order terms that are not captured by the analytic formulae used to fit the ETV curves.