Twelve-year timing data of PSR J2222−0137, for the ELL1H+ timing model where we used the DMX model and fit for position and proper motion (middle column in Table 3). Top panel: DM offsets relative to the reference DM (3.2805 cm⁻³ pc) as a function of date. Middle and bottom panels: timing residuals as a function of date (middle) and orbital phase (bottom, measured from ascending node). The residuals are displayed with different offsets for each instrument: EFF – Effelsberg; JB – Lovell telescope (Jodrell Bank); NCY-S – Nançay at the S band; NCY-L – Nançay at the L band; GBT-820 – GBT at 800 MHz; and GBT-1500 – GBT at 1500 MHz.