Line profile modelled at the Resolve resolution including all subcomponents of Fe IV (Palmeri et al. 2003). Profiles are shown for the three orbital phases of the observations and three different scenarios: from top to bottom: accretion onto a magnetic white dwarf, accretion onto a non-magnetic white dwarf, and interaction between the Be star and its disc (see Rauw 2025). The colour convention follows Figs. 1 and 3.