Narrow-band images and inverted velocity maps where downflowing structures matching the SDF/SSUB pairs are highlighted for four different cases (A to D as labelled). First column: upflowing stage of the SDFs as seen at −220 mÅ, 90 s before the SSUB. Second column: velocity map obtained from the respective inversions (i.e. from the full spectra and full FOV 90 s before the SSUBs) where the values were averaged between log τ₅₀₀ = −4.5 and −5.5. Third column: down phase of the SDF, consecutive with the SSUB, as seen at +220 mÅ. Fourth column: SSUB, as visible at −220 mÅ. Last column: velocity map obtained from the inversions where the values were averaged between log τ₅₀₀ = −4 and −5. The contours highlight continuous regions automatically selected based on the presence of a flowing area that differs from the background. The arrow in case A highlights the “flash” location plotted in Figs. 5 and 7.