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ASASSN-14ko was identified as an abnormal periodic nuclear transient with apotential decreasing period. Its outbursts in the optical and UV bands havedisplayed a consistent and smooth "fast-rise and slow-decay" pattern since itsdiscovery, which has recently experienced an unexpected alteration in the lasttwo epochs, as revealed by our proposed high-cadence Swift observations. Thenew light curve profiles show a bump during the rising stages and arebrightening during the declining stages, making them much broader andsymmetrical than the previous ones. In the last two epochs, there is nosignificant difference in the X-ray spectral slope compared to the previousone, and its overall luminosity is lower than those of the previous epochs. Theenergy released in the early bump and rebrightening phases ($\sim10^{50}$ erg)could be due to collision of the stripped stream from partial tidal disruptionevents (pTDEs) with an expanded accretion disk. We also discussed otherpotential explanations, such as disk instability and star-disk collisions.Further high-cadence multi-wavelength observations of subsequent cycles areencouraged to comprehend the unique periodic source with its new intriguingfeatures.

Dissonance in harmony: The UV/optical periodic outbursts of ASASSN-14ko exhibit repeated bumps and rebrightenings