Position-velocity (PV) diagrams of SiO at 86.8 GHz and SO at 99.3 GHz and 109.252 GHz taken along the solid black arrows labelled aB1 and aR1 in Fig. 2. Here, the position labelled 0 corresponds to the centre of the hot core. Contours are at 5σ, 25σ, and then increase by a factor 2, where σ = 0.12 K for SiO and 0.5 K and 0.32 K for the two SO transitions, respectively, and was measured in an emission-free region in the respective data cubes. Pixels with intensities less than −30σ are shown in black. The positions N1SE1 and N1NW3 are indicated with light-blue solid lines. Regions close to the centre and those containing contaminating emission from other species are masked in white. The white dashed line marks an average systemic velocity of 62 km s⁻¹. The frequency and upper-level energy of the respective transition are written in the top left corner. Highlighted features in blue-shifted emission towards the south-east (SE, in the position-position maps) include B1 (elongated along velocity axis) and B2 (elongated along both axes). Intensity peaks in red-shifted emission towards the north-west (NW) are labelled R1 and R2, and red-shifted emission features close to the systemic velocity are labelled R3 (NW) and R4 (SE).