Accretion disc model fit to the optical/NIR emission of VIK J2318−31. Top panel: rest-frame optical-UV luminosities of VIK J2318−31 (cyan points) together with the best-fit SS AD model (solid black line). The shaded blue area represents the model within the 16th and 84th percentiles. The hatched yellow region at ν > 3.3 × 10¹⁵ Hz indicates frequencies higher than the Lyα emission line, which not accessible at high redshift due to the absorption from the IGM. Bottom panels: corner plot with the posterior distributions of the parameters used in the fit. Dashed vertical lines indicate the 16th, 50th and 84th percentiles.