# 490d Mirror checkpoint after C471

25 September 2026 UTC. **C471 complete; C472 unexecuted.** 8 steps remain in the current authorization. Current decisions override archived next-step text.

## Current result

All three1250 outputs have a matched-context MT Shem-death versus SP-primary/LXX-OFF Shem-birth binding, giving600+650. Their endpoint changes are−150/−50,−64/+36 and−128/−28. The first two-K ancestry fails at missing2093/3151; the third fails integrality at every fixed first pivot; only the established middle case has a sourced predecessor.

## Earlier results in this batch

**C470**: All 51 sourced 1150-year coordinate pairs (101 label pairs) produce 408 fixed-pivot E trials: 16 have integer outputs and three have both outputs sourced. The admitted pairs are1955/3105→1805/3055 at3680,2020/3170→1956/3206 at2756, and2148/3298→2020/3270 at3620. Only the middle case has a complete sourced2K predecessor,2148/3206 at3620.

## Baseline and standing scope

C469 is the authenticated baseline. Its checkpoint is frozen in sources/C469_CHECKPOINT.md. The fixed local reflection centers are 3188, 3190, 3248 and 3250, each an existing MT Noah birth record. The 528 labelled Noah/Shem/Flood records occupy 373 integer BC coordinates. These local source comparisons do not replace the January-AD1 global Mirror. C469 establishes the complete shared-word interval ladder 2148/3206→2020/3170→1956/3206, spanning 1058→1150→1250 at pivots 3620 then 2756. Its source certificate has seven distinct coordinates. C465’s mixed-cycle 12→12 label count covers vertices only; including its operator anchors gives 48→12, as clarified in C469. The SKL appendix and corrected LXX8464 observations remain supplemental; no redirection follows. C432’s E excerpt locator was corrected in C434 and carried through C469 to File_46 L3, lines117–133; prior arithmetic already used25/23.

Mirror/529 focus: K=529, E=25/23, P=70/69; J=300/299 remains File02 gap conversion, not a calendar date operator or Residue Protocol. Regular Gears are Noah/Shem/Flood only. SP person companions are local to Noah/Shem; Flood close is an independent event boundary. Both500/100 and502/98 bindings remain valid; SP primary Noah death retains its inclusive/harmonic qualification. LXX native Cainan is ON; OFF is theoretical removal. Global paired Mirror January AD1; local junction January AD2; no civil year zero. No new source point, phase, fitted axis, upstream/cumulative Gear, primer reopening or canonical/graph edit. Capture now; canonize later. Coordinates, source labels, context aliases and derived comparisons remain distinct. Counts are not independent historical witnesses.

## Limits and verification

The650 offset is between normalized MT and SP/LXX-OFF states. LXX native Cainan-ON input alternatives at3298 do not make its C0 output a native-ON record. No missing predecessor is generated or admitted.

52 calculation checks and 21 source/predecessor authentication checks passed. Main result files replay byte for byte. These are root-agent checks, not an independent-agent review or independent historical witnesses.

## Best next bounded step

C472: Census all1250-year source pairs and their labelled role/context families, locate the three admitted E outputs, and distinguish the matched Shem600+650 family from other1250 comparisons and aliases.

The three outputs share a clear source structure. The complete1250 inventory will show whether that structure accounts for all such spans or only one identifiable family.

Continue within the authorized batch and reassess after the next result.