TIC 71503196.01: a 2.9 Earth-radius planet candidate on a 1.57-day orbit around a nearby M dwarf, found in TESS full-frame images

We report a transiting planet candidate around TIC 71503196 (Gaia DR3 6881482024264027136), a T = 13.3 M dwarf at 61.5 pc, found by Tessa, an open search of TESS full-frame-image light curves of nearby K and M dwarfs that were mostly never observed at 2-minute cadence. Data from 3 sectors show 36 transits with period P = 1.569905 ± 0.000009 d, depth 6454 ppm and duration 1.20 h (SNR 16.6), implying a planet radius of 2.86+0.12−0.08 R⊕. The signal passes every test available to us: odd and even transits agree (0.6σ) and there is no significant secondary eclipse (SNR 2.2); the depth is consistent across sectors (p = 0.02); the stellar density implied by the transit shape matches the catalogue value (ratio 1.21, 68% interval 0.80–1.42); Gaia DR3 astrometry (RUWE 1.15) shows no sign that the target is a binary; in a leave-one-season-out test, each of 3 seasons is predicted from the others and shows the dip at the predicted times; the identical search on this star's upside-down light curve finds nothing stronger than SNR 8.0, against 16.6 for the dip; TRICERATOPS gives FPP = 0.009 and NFPP = 4.3e-04, below the statistical-validation bar (FPP < 0.015, NFPP < 0.001). The candidate matches no known planet, TOI, CTOI, catalogued eclipsing binary or variable star. Other searches have also reported it (the ExoMiner++ 2.0 catalogue (Zenodo 17707413)); Tessa found it independently, and this note adds its own vetting and predictions. We give an ephemeris and predicted transit times (timing uncertainty ≈8 min) for TESS Sector 116, which observes the star from 2027-04-12 to 2027-05-09, and for ground-based observations, and set out in advance the criterion by which new data will test the prediction. Files: the preprint (PDF); every predicted transit to 2027-06-30, with ground-site observability (CSV); and the candidate parameters (JSON).