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tokens: zero frequency lag component. Similarly, the autocorrelation of the (unfiltered) 2019-03-07 epoch (left-hand panels of Fig. 7 ) shows a strong zero frequency lag peak centred at 5.447 ± 0.008 h. Note that the quoted uncertainties are estimates based on the sample distribution of periods from the simple top-hat pulse model described in Sections 3.1.1 and 3.1.2 . Figure 7. Two-dimensional autocorrelation function, and the corresponding zero frequency lag components for the 2019-03-07 (left-hand panels) and 2018-10-02 epochs (right-hand panels). Dashed lines indicate the time lag of the major peak in the autocorrelation, which measures the periodicity of the pulses. The dash–dotted lines in the autocorrelation of 2019-03-07 are spaced every h from the zero time lag component, and around the major peak at a time lag of 5.447 h, and show the quasi-periodic nature of the pulses 19-1A, B, C and 19-2A, B, and C. The pulse periods measured between the two epochs are consistent with one another, and consistent with the 5.4432 ± 0.0072 h period measured by Barnes et al. ( 2017 ). We note that this disambiguates which component of the L726-8AB binary the emission originates from – the primary component BL Ceti (L726 − 8A) is also known to be active at radio frequencies (e.g. Gary et al. 1982 ), and is separated from UV Ceti by ∼4′′, well below the ∼15′′ resolution of our ASKAP observations. However, BL Ceti has a rotational period of 5.832 ± 0.012 h (Barnes et al. 2017 ). Along with the h periodicity revealed by the autocorrelation of the 2019-03-07 observation, there are also three minor peaks in the autocorrelation spaced every h from the zero time lag component, and to either side of the primary period of h. This gives strong evidence for the quasi-periodic nature of the faint pulses 19-1A, B, C and 19-2A, B, C. 3.3 Comparison of the two epochs We find notable similarities between the pulses occurring in both epochs when inspecting the dynamic spectra side by side. Most striking is the faint pulses occurring in both epochs: 18-1A, 18-2A, and 19-1A, B, C, 19-2A, B, C – all these pulses have very similar drift rates (, virtually indistinguishable within the bandwidth of our observations), durations (∼12 min), and are similar in their average flux densities (∼40–50 mJy). However, in the 2019-03-07 epoch, three faint pulses with equal drift rates occur every rotation, where as in 2018-10-02 only one faint, negative-drifting pulse occurs per rotation. Pulses 19-1B and 19-2B are morphologically most similar to the faint pulses 18-1A and 18-2A occurring once per rotation in the 2018-10-02 epoch, 18-1A and 18-2A. Furthermore, the time difference between 19-1B and 19-1D, and 19-2B and 19-2D (∼60 min) is similar to the time difference between 18-1A and 18-1B (∼50 min). While there are some morphological similarities between the bright pulses in both epochs, the bright burst in 2018-10-02 has a slower bulk drift rate, a longer duration, and overall a more complex