Four transits of HD 332231 b. Top: transit data points from the TESS light curve after correction using the GP model seen in Fig. 1. The grey line is the best-fitting light curve model. Bottom: residuals from subtracting the best-fitting model from the data. In each top panel, we show an error bar that is representative of the error from this particular selection of data. We added the photometric jitter in quadrature (shown in black) to the nominal error (coloured).