Top panel: comparison of the spectra of the first and second epoch afterglow and the spectrum of the host galaxy at λ< 5000 Å, each binned by 100 Å, together with the measured VLT/FORS2 u-band magnitude of the host. The consistent lower flux in the first epoch afterglow spectrum below 4000 Å is due to the host galaxy being partly outside of the slit (see Fig. 2). Bottom panel: first and second epoch afterglow spectra with the flux of the host galaxy subtracted. Overplotted is the 2715 Å extinction bump model from Fynbo et al. (2014), which can now be securely excluded as the scenario causing the steep extinction.