Upper left panel: observed (black solid line) and preferred steady-state NLTE model (red solid line) K-band spectra at days 206 and 200, respectively. Upper right panel: the same, but with the CO LTE model emission added to the steady-state NLTE model spectra. The CO overtone band heads have been marked by red dashed lines and the steady-state NLTE model spectra flux calibrated with the observed K-band flux at day 206. Lower panel: observed (black solid line) H- and K-band spectrum at day 89 as compared to a blackbody fit to the continuum (red solid line).