Additional Transit-like Signals in TESS Photometry of TOI-6898 and LHS 1815

I report two transit-like signals found in public TESS photometry of stars that already host a transiting planet or planet candidates. In TOI-6898 (TIC 441158994), a 5.4687 d signal about 500 ppm deep appears in all five observed sectors (2018-2026) and would correspond to a 1.55 +/- 0.18 Earth-radius planet if it is on the target. In LHS 1815 (TIC 260004324), a 2.4734 d signal of about 80-95 ppm (0.50 Earth radii if on the target) is present across 42 sectors but is shallow, processing dependent and tentative, and it misses a pre-set depth criterion. Both periods are recovered by two search codes and by blind searches with observing years withheld, but every test uses the discovery data. No statistical validation is claimed; neither signal is a validated or confirmed planet. This record contains the note (note.pdf) and one archive with the code, the per-target results for all 69 searched hosts, the frozen ephemerides, predicted transit times to the end of 2028 and a pre-registered scoring rule with four fixed outcomes. TESS Sector 116 (2027 April 12 to May 10) gives the first independent test of the TOI-6898 signal; the outcome will be reported in a new version of this record whatever it is. Start with README.md inside the archive. The analysis code was written and run with the AI models ChatGPT Sol 6.1 (OpenAI) and Claude Opus 5.5 (Anthropic) under the author's direction. This is a preprint and has not been peer reviewed.