Transverse P–V diagrams of CH₃OH (2_2,1,0−3_1,2,0), H¹³CN (4−3), and SO (8₉−7₈) perpendicular to the jet axis, at projected offsets ɀ_proj ~ 30, 60, 90, and 120 au from the continuum peak, and averaged over a slit width of ~1 beam. Cuts through the red (resp. blue) lobe are labeled SE for southeast (resp. NW for northwest). The black solid curves show predictions for a thin shell model of rotating conical flow with a base radius of ~19 au, obtained by fitting the SE P–V cuts of CH₃OH and H¹³CN (see green curves in Fig. A.2). The same model is overlaid in dashed lines on SE P–V cuts of SO for comparison.