The measured secondary eclipse phase of GG Lup increased in four TESS sectors from 2019 to 2026

We measure local eclipse phases of GG Lup, TIC 148158540, in four public two-minute TESS SPOC light curves. Sectors 11, 38, 65, and 103 cover 2019, 2021, 2023, and 2026. A time-coverage audit keeps 86 eclipse windows and 30 complete groups of a secondary eclipse between adjacent primary eclipses. The midpoint of the two half-depth crossings defines each event time. The mean secondary phase increases from 0.4088535 to 0.4329318. At a fixed period scale of 1.8495996 days, the increase is 64.13 minutes. Twenty-six usable reduction configurations at three depths give 78 measurement definitions. All give increases, from 63.64 to 64.55 minutes. This is a sensitivity range, not a confidence interval. An orbit-block bootstrap gives a sampling standard deviation of 0.49 minutes for the main endpoint change; it excludes common profile errors. Synthetic eclipses on the real observing times check the method and show the effect of a sample brightness signal. An edge-on point-conjunction model, anchored in 2019, predicts increases from 48.34 to 69.77 minutes over a bracket of published eccentricities and apsidal rates. Its central prediction is 4.30 minutes below the 2026 result. This approximate comparison does not establish an unexplained source. Apsidal motion in GG Lup is known. The contribution adds later timing constraints, a complete event and fit audit, depth tests, and an offline reproducible data package. Original FITS data, provenance hashes, source code, bootstrap samples, controls, and figures are preserved.

GG Lupi · TESS · eclipsing binaries · eclipse timing · apsidal motion · public astronomical data · reproducible research