The AS Cam eclipse gap increased by 73 s/year in five 2019–2024 TESS visits with fixed profile fits

AS Cam has disputed rates of orbital rotation and a known shared eclipse delay. We reuse 50 eclipse centres from five TESS visits in 2019–2024. We fit separate shared clock offsets and drifts in each visit. The secondary to primary clock difference increases by 73.5 ± 8.1 seconds per year. The error assumes fixed eclipse profiles and independent binary cycle blocks. Seven extraction choices give 71.4 to 80.1 seconds per year. Eleven complete eclipse triplets give a check of 76.3 seconds per year. The 2019 visit supplies much of the time span: its removal gives 30.9 ± 29.0 seconds per year. At constant eccentricity 0.164, the main slope maps to orbital rotation of 0.154 ± 0.017 degrees per year. An eccentricity increase can give the same slope at a higher rotation rate. We supply this conditional orbit constraint, event weights, delay leakage checks, figures, source code, and the unchanged signed input record. The result does not establish a unique orbit model or a new companion. Changes in stellar pulses or eclipse shape remain outside the reported error.

AS Camelopardalis · TESS · eclipsing binaries · apsidal motion · eccentricity · eclipse timing · reproducible astronomy