L1 periodogram analysis of LCOGT light curves and trailed plot of He I line. Top: time series of EW measured for He I, Paβ, Paγ, and Paδ lines. Middle: L1 periodogram of EW. A clear peak is detected in the strongest line tracing accretion (Paβ) at ~27.0 d. Additional peaks that are relatively significant are seen at 7.2 d, 9.1 d (spot), 11.6 d, 18.5 d (see text). Bottom: trailed plot of the He I line phased at a period of 19.5 d showing high-velocity outflows traced by the blue absorption component in the line. The colour bar represents the normalised flux.