Location of J1257 (purple region) on the T_dur–T_rec plane defined by the current QPE population (light blue regions). The grey area represents events with T_dur ≥ T_rec that cannot be classified as well-isolated QPEs. We point out that QPEs with long recurrence times and short durations, which would populate the lower-right corner of the plane, are extremely difficult to detect; therefore, the clear correlation seen in the QPE timing plane could be affected, at least partly, by an observational bias. QPE data are taken from Arcodia et al. (2025). The dashed line is a best-fitting relation of the form $T_{\mathrm{dur}}\propto T_{\mathrm{rec}}^p$ resulting in p = 0.9 ± 0.1, that is, in a relation consistent with being linear.