C66 — The 299 midpoint expands to 325+325 without inheriting its event name

22 September 2026 · Step 4 of the authorized ten-step Mirror continuation (C63–C72).

The phase-preserving 25/23 map carries the midpoint of the MT Flood–MT Noah comparison to the midpoint between MT Noah and SP primary Noah:

N02's image is centred at 3381; N04's at 3383. The midpoint relation holds separately for Tishri and Nisan, and both new formal pairs remain half a year wide. Thus preserving the midpoint shape and seasonal phase is automatic under the declared affine action.

The named event does not transfer automatically. The retained SP Noah-death field is 2755–2760 when primary/companion stations and the three Gears are included. Neither image belongs to that field. The original midpoint is a sourced SP companion death; the expanded midpoint is a derived comparison coordinate between two sourced births. No new historical event at 3381/3383 is established here, and no all-repository search is claimed.

This separates the useful algebra from source admission. The endpoints MT Noah and SP Noah survive this expansion with their existing identities; the middle point preserves the 1:1 division but loses the original event label. An exact phase-preserving map therefore need not preserve every typed source node.

Validation. 10 exact arithmetic/structural checks passed. The 14 frozen dependencies passed hash verification; all three generated outputs replayed byte for byte in isolation, and the original dependencies remained unchanged. This step reads completed certificates and does not execute their campaigns.

Scope and provenance. Controlling File_18 and File_09 remain unchanged. Regular Gears apply only to Noah/Shem/Flood; SP person companions only to Noah/Shem. Creation and Conquest fields remain fixed. Native LXX ON, explicitly derived OFF, independent Flood start/close, and paired suffix inversion at January AD 1 remain in force. No civil year zero, upstream Gear transport, primers, Rounded campaign, or localized −33 is introduced. These are new continuation reports, not recovered historical Reports 11–25. Evidence is conditional on the supplied project model, not a proof of literary intention or independent historical dating.

Source locators. File_09 §3 and Appendix A (paired Mirror and exact phase); File_18 §§2.1.3, 2.4, 3.1 and 3.2 (regular source bindings and seasonal limits); frozen C15/C16/C22/C43/C50/C61/C62 certificates (retained graph and phase); C01/C04/C05 reports (completed expansions and their source limits). The declared phase model does not infer an unstated birthday or event month from an annual source row.

Best next bounded step — High sufficient. Compare the fixed-Creation expansion with the existing apparent-anchor map joining the 12-fold and 13-fold constructions.