Top row: evolution of a region of Ca ii H data displaying an umbral flash followed closely by a SSUB. Each frame is separated by 16.8 s. The large and small boxes in the left-hand panel indicate the regions which are averaged to create the lightcurves plotted in the bottom panel. Bottom row: a lightcurve plotting the intensity evolution of the umbral flash (solid line) and SSUB (dashed line). The solid vertical lines indicate the frames plotted in the top row. A second flash and SSUB pairing is also evident between 10:51 UT and 10:52 UT. A distinct time-lag between the peak intensities of the phenomena can be identified for both pairings.