Held-out TESS Sectors 97-107 support the SPOC Sectors 1-96 ephemeris over the ExoFOP ephemeris for 9 of 10 decided TOIs, give P = 19.6658 d for TOI-2326.01, and recover a 3.145-d candidate at TOI-7387

We tested periodic transit signals (TCEs) from the TESS SPOC multi-sector search of Sectors 1-96 with data that this search did not use: SPOC 2-min light curves of Sectors 97-107 and QLP light curves of Sectors 97-105. We kept the transit shape and ephemeris fixed and fitted one depth scale A (A = 1: same depth; A = 0: no transit). We wrote the decision rules before we fitted the candidates. Calibration on 318 TCEs: the test recovers 235 of 243 (96.7 %) decided known or confirmed planets, but also 39 of 44 (88.6 %) decided false positives. Thus the test shows that a signal continues; it does not show that the signal is a planet. Ephemeris audit: we compared 1759 ExoFOP TOIs with the SPOC TCEs on the same star. 193 pairs have periods that differ by more than 5 sigma. For 26 pairs, the two ephemerides predict held-out transits more than one transit duration apart; 14 of these have held-out data. The held-out data decide 10 of the 14. For 9 TOIs (1130.02, 2922.01, 2968.01, 3434.01, 4650.01, 5014.01, 5019.01, 5023.01, 5055.01) the SPOC ephemeris is supported and the ExoFOP ephemeris is not. For TOI-2966.01 the ExoFOP ephemeris is supported. TOI-4650.01: P = 2.6576562 +/- 0.0000018 d, T0 = 3155.54341 +/- 0.00057 BTJD; in Sector 106, A = 1.009 +/- 0.030 at the SPOC ephemeris and -0.11 +/- 0.09 at the ExoFOP ephemeris. TOI-2326.01: six transits give P = 19.665777 +/- 0.000037 d, one third of the ExoFOP period; the data exclude the aliases P/j for j = 2-40. New candidate: of 220 vetted TCEs without a TOI match, 167 have held-out data. TIC 300381700 TCE-02 (P = 3.14524 d, 1410 ppm) is on the star of TOI-7387.01. With the TOI-7387.01 transits masked, Sectors 97-98 give A = 0.93 +/- 0.10 and an empirical SNR of 10.1 in 22 transits. The signal is grazing (b = 0.98) and V-shaped, so a blended eclipsing binary is possible. Limits: the audit, the tiers and the case studies are post hoc; QLP has no calibration; the period uncertainties assume a linear ephemeris. The package contains the code, derived tables, figures, logs and the source URLs and SHA-256 sums of the external data.

TESS · transiting exoplanets · TOI ephemeris · held-out validation · SPOC · QLP · transit timing · period alias · TOI-4650 · TOI-2326 · TOI-7387 · TIC 300381700 · planet candidates · false positives · pre-registration