# 490d Mirror checkpoint after C311

24 September 2026. Latest completed: **C311 — Source-rule audit of the MT-to-SP context switch.** C312 is proposed and unexecuted.

## Restart here

Read the C311 report and this checkpoint, then the frozen C310 checkpoint for the full inherited synthesis. The C311 evidence ZIP includes the three audited sources, C302/C310 target data, C310 certificate/results/checkpoint, the audit plan, source reviews, exact excerpts, checker, replay and integrity records. Retrieve earlier dependencies selectively. Do not rerun C277–C310 or follow superseded next-step paragraphs.

C277–C310 was a completed 34-step batch. The latest user “Proceed” authorized this one C311 audit after recovery. C311 did not repeat the batch, begin C312, revisit the original AD1905–1911 proposal or enlarge the endpoint census.

## C311 result

File_18 supports the regular endpoint states and qualified comparisons. File_09 permits source-qualified comparisons while keeping cumulative boundary nodes distinct from regular biographies. AXIS_REPORT supplies the fixed bridge/anchor algebra and separately selected contexts. **No pre-existing rule was located in these three documents prescribing C310's exact annual-index-dependent MT-to-SP context and event-role switch.**

Keep the distinction between documented ingredients, generic comparison permission and a specific selector. The first two are supported; the third remains unestablished. This bounded absence finding neither invalidates the arithmetic nor proves that no rule exists elsewhere. File_18 describes the SP table-derived stations as source-controlled, not six independently attested source states. The LXX OFF cumulative Shem/Flood field is an inherited derivation, not a verbatim native File_18 row.

## Retained cross-bridge result

Regular W8464 to reflected Q6 and cumulative W12696 to reflected Q1406 yield C−B=2832. C301 found 28 labelled/18 coordinate point matches. C302 retained 12 labelled/eight coordinate 600-year segments: MT4, SP5, LXX3. Cumulative LXX OFF is Shem5890−j/Flood5290−j, j0…7.

C310's unique minimum context-family cover is MT Noah birth→Flood start, OFF/Terah0/full430, at j0/2; plus SP Shem birth→death, OFF/Terah+60/minimum215, at j3…7. LXX Shem-life labels j3/5/7 alias SP coordinates. Keep each segment's Gear and rail labels. Index j1 still requires 3057/2457 with the upper endpoint absent. This is an exact **composite comparison cover**, without an established source-prescribed switch.

## Core 529 findings remain inherited

K=529. C286's fixed census has 256 cumulative state/index pairs ×528 regular records =135168 comparisons, with 12 labelled/10 coordinate all-K paths. The source-qualified mixed route is 2K+15K=17K: 598+460=1058 and 8395−460=7935. C276 retains the selected cross-index placement δ=h−f=598 as a premise beyond source transport alone.

C287 normal form: (S,F,R,N)=(−12K,−10K,5K,7K)+i, with typed cumulative LXX ON Shem, cumulative LXX OFF Flood, regular MT Flood ON/+60/full430, and regular SP Noah OFF/0/full430 (LXX primary aliases). S/F/R exist at i0…5; N only at i2…5. Missing3703/3704 remain absent. Six pairwise durations have rank3, leaving a common translation free. The inherited 16K interlacing yields (4,5,6,7)K+i.

C294's fixed8K reflection has admitted centers527,1587,2645,3705 and gaps1060,1058,1060. C295's 2304 combinations contain one fixed-reflection and four all-K configurations, with zero joint configurations. C290 preserves the distinction between center matches and phase pairs: expansion25/23 changes half-year width to25/46; translation preserves width. Mirror reverses seasonal ancestry.

C304 retains C127 N01/N02 overlaps at cumulative Flood5288/5287 with direct17K and868+13K+1248. Only N02 carries299+299+650 via SP Noah death2757 and MT Noah3056. C307's typed system gives n−p=595+2i: admitted i2/3 yield599/601; exact600 requires inadmissible half-index2.5. C306's alternative600 choices each disturb a fixed interface by±1. C308's Q1446-only change gives offset2792, eleven labelled/eight coordinate points, all SP OFF cumulative Shem, and zero complete600 segments.

## Controls and corrected supplement

Mirror and529 remain the focus. K=529, E=25/23, P=70/69. Global Mirror January AD1; local junction x=1, January AD2; no civil year zero. Regular Gears remain Noah/Shem/Flood only. SP −1 remains local to SP Noah/Shem. No cumulative/upstream Gear operation, canonical/graph changes, primer reopening or new global axis/z-law. Capture now; canonize later. Co-located coordinates do not identify events, and derived equalities are not additional independent witnesses.

Supplement for awareness: under W8464, LXX Creation5494 BC→AD2970 compared with reflected ConquestAD1406 gives1564=68×23→1700 by25/23. Jared4534 BC→AD3930 compared with reflected ExodusAD1446 gives2484=108×23→2700. LXX Creation→Jared960 versus MT460; MT/LXX offsets1380 at Creation and880 at Jared. Difference960−40=920→1000. Earlier AD3746/2300 is superseded. This supplement does not redirect the work.

The C-series remains distinct from original unprefixed Reports01–10 and unestablished interrupted original Reports11–25. This checkpoint does not alter the archive availability findings recorded at recovery.

## Verification and next step

C311 passed15 citation-binding/retained arithmetic-domain assertions and10 source-authentication checks; its two outputs replay byte identically. Separate source reviewers read File_18 and File_09; the author integrated the axis report. This is not an independent mathematical or historical corroboration. Source-rule absence remains a qualitative, three-document conclusion. Standing inputs are unchanged; C127 retains208 nodes/382 duration edges.

**C312, proposed only:** test one uniform, source-labelled same-Gear transport between existing MT Noah→Flood and SP Shem-life600 pairs against the existing MT/LXX cumulative weave and its field boundary. Include primary and local companion rails; keep the finite inputs fixed and record failures. This is the next constrained structural question after the selector audit. Do not add endpoints, fit anchors or equate a successful transport with a source-prescribed selector. High is sufficient. **C312 has not been executed.**