Top: folded Swift/BAT daily light curve using 32 phase bins with a period of 4.56993 d and mid-eclipse reference time of 55083.82 BMJD (Coley et al. 2015). The vertical light red stripes correspond to the six XMM-Newton observations used in this paper with their widths representing their final exposure times after GTI filtering. Bottom: neutron star spin periods for each observation, estimated by fitting a Lorentzian profile to the χ² distribution of the period search. Observation #74a (eclipse) was not included in the analysis. Average spin periods of 140.015 ± 0.0008 s and 139.81 ± 0.02 s before and after the eclipse, respectively, are registered (excluding Obs #26, as it corresponds to a different epoch). Averages are indicated with dashed lines.