C27 — Civil-year counting agrees with the Mirror coordinates
22 September 2026 · Step 5 of the authorized 30-step Mirror continuation (C23–C52).
For a left endpoint −b and right endpoint +a, the paired endpoints are (b+1)t/b n BC and AD a t/(a+1)n. Both same-season civil counts give b+a:
(b+1)+a−1 = b+(a+1)−1 = b+a.
| Branch | Family | BC pair | AD pair | Elapsed |
|---|---|---|---|---|
| N01 | 13 | 4421t/4420n BC | AD 2457t/2458n | 6877 |
| N01 | 17 | 5289t/5288n BC | AD 3705t/3706n | 8993 |
| N01 | 20 | 5293t/5292n BC | AD 5288t/5289n | 10580 |
| N02 | 13 | 4420t/4419n BC | AD 2458t/2459n | 6877 |
| N02 | 17 | 5288t/5287n BC | AD 3706t/3707n | 8993 |
| N02 | 20 | 5294t/5293n BC | AD 5287t/5288n | 10580 |
| N03 | 13 | 4419t/4418n BC | AD 2459t/2460n | 6877 |
| N03 | 17 | 5287t/5286n BC | AD 3707t/3708n | 8993 |
| N03 | 20 | 5295t/5294n BC | AD 5286t/5287n | 10580 |
| N04 | 13 | 4418t/4417n BC | AD 2460t/2461n | 6877 |
| N04 | 17 | 5286t/5285n BC | AD 3708t/3709n | 8993 |
| N04 | 20 | 5296t/5295n BC | AD 5285t/5286n | 10580 |
Thus N02's Creation-to-reflected-Flood interval is 4420t/4419n BC to AD 2458t/2459n: 4420+2458−1=6877 and 4419+2459−1=6877. Subtracting one from the two signed-coordinate magnitudes instead would give 6876 and mix the conventions.
Zero in this geometry denotes the paired axis, not a civil year-zero date. Reflections invert the seasonal pair; they do not preserve both suffix numerals. The checks use only the already registered cross-axis paths and do not infer new event dates from a numeric centre.
Validation. 13 exact arithmetic/structural checks passed. The ten 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 §3.1 (paired Mirror); File_18 §§2.1.3, 3.1–3.2, 6B and 6D (qualified regular and cumulative fields); frozen C15 typed graph, C16 domain certificate, and C22 reduced scale/constraint certificates.
Best next bounded step — High sufficient. Locate the 13-fold interval inside the 17-fold interval, retaining the unequal flanks.