Evolution during the XMM-Newton observation of the bolometric bbody luminosity compared to the temperature in both spectral models, fitted with a power law. The colours are used to identify individual time windows (see Fig. 7). Top panel: TBabs × zashift × bbody model. The red line corresponds to a fit using all the data points, with the quiescent state in dark red being a visible outlier. The grey line corresponds to the fit performed excluding the quiescent state. The shaded areas and the uncertainty on the power-law index correspond to a 1σ confidence level. Bottom panel: TBabs × zashift × (diskbb + bbody) model.