(a) Hα line as seen in both X-shooter spectra, normalised for comparison. The second observation shows a stronger and single-peaked line profile, compared to an asymmetric line profile in the first data set. The asymmetry is likely due to the contribution of He IIλ6560, also being in emission. (b) He IIλ4686 and He Iλ4713 are in emission, in both X-shooter spectra, but without as much variability. We normalised the two spectral continua relative to each other to compare the behaviour of the emission lines.