Time series of 0.66 km s⁻¹ feature. The solid lines show every 130.6 d from MJD = 56342.3, which is the first peak of the best-fitting power function and the dotted lines are in the middle of the solid lines. Labels on the upper axis indicate the beginning of each year. The thick solid lines around MJD = 56734, 56865, and 59607 indicate that a flux density over 3σ was not detected during the eight days before and after the expected flare date.