Column density profiles of H₂CO, CH₃OH, and CH₂DOH for the 1D-4 model for four different time steps ranging from 10⁵ yr to 10⁶ yr. The lines with markers show the modelled results, integrated along the line of sight and convolved with a 30″ beam. The solid lines show the observationally obtained column density profiles obtained by Chacón-Tanarro et al. (2019) by taking a cut through the dust and methanol peaks. The grey-shaded areas indicate the error bars of the column densities. The position of the dust peak is at r = 0 AU, while r > 0 AU is the direction towards the methanol peak.