Details of some emission lines in the spectra of both epochs. Zero velocities of He II–10124, He I–10830, and He II–21885 are marked with dash-dotted lines. We note that all H and He lines display clear red skewed profiles during epoch 1. Top left: He II–4686 + Bowen blend. The Bowen blend exhibits narrow emission components during epoch 2, which are not present in epoch 1. Top right: Hα profile. The emission is embedded in a broad absorption feature. The normalised spectra of an A2V star, with a scale-corrected contribution, are shown vertically displaced at 0.9 for comparison. Middle left: Paδ emission line and He II–10124 at ∼2200 km s⁻¹. We note that Paδ shows a strong emission blue wing compared with the He II line. Middle right: Paγ and He I–10830 lines. We note that Paγ exhibits a blue emission wing. Bottom left: Brγ and He II–21885 lines. Bottom right: Paδ (solid) and Brγ (dotted) emission lines in epoch 1.