Directional Reanalysis of the Earth Flyby Anomaly and a Prospective Prediction for JUICE 2026

A retrospective panel of nine Earth flybys from 1990 to 2013 is examined using previously reconstructed near-perigee trajectory directions and the horizontal direction of the International Geomagnetic Reference Field (IGRF) main field. The proposed rule assigns anomaly ON to a negative horizontal velocity-field dot product and OFF to a positive dot product. Under the manuscript's inherited historical labels, the rule agrees with eight of nine events. An unrestricted geographic north-south sign diagnostic also agrees with eight of nine. These are descriptive, outcome-inspected comparisons, not independent validation. Cassini's thruster contamination and its post hoc exclusion, Galileo-II's drag qualification, and a spacecraft-specific explanation proposed for Rosetta-I limit interpretation of the labels. The historical table is retained from an observer-ephemeris reconstruction; independent geometric-state-vector verification remains outstanding. Earlier environmental and memory tests are reported as limited internal diagnostics rather than a comprehensive exclusion of alternative mechanisms. For JUICE 2026, the adopted JPL heading and ESA/SOC closest-approach geometry give a normalized horizontal dot product of approximately +0.156121 and an angular sign margin of 8.98°. The preserved prediction is |Δv∞| < 0.5 mm s⁻¹, an operational classification rather than an exact zero or a derived magnitude law. The separately frozen north-south competitor is outside its stated applicability domain. The original V1/V2 archives, their verified hashes, a distinction between local recording and public registration, and the official-source adjudication procedure are specified. A null result would offer only weak consistency evidence at the adopted high altitude. A reliably established, appropriately defined residual at or above the threshold would contradict the primary forecast and will not be rescued by auxiliary environmental variables. CDI and 6π⁵ remain hypothetical interpretive language, not an established force law.