# C306 author review

Question: Can existing selectors or seasonal components give600 while retaining both fixed interface equations?

Conclusion: All four admitted600 selector alternatives change one fixed interface by±1; actual phase components do not give600 for either jointly fixed pair.

The exact results were inspected against the source register and independently expressed domain identities in the checker. The second run verifies deterministic reproduction, not independent scientific review. No new agent review is claimed.

Limits:

- Alternative source-admitted selectors change a premise even when endpoints are close.
- The phase audit does not permit arbitrary seasonal reattachment of the fixed anchors.
- No new axis, bridge or annual center is adopted.

The report and checkpoint are authored interpretations. The verifier authenticates the supplied inputs and calculations; it does not prove historical intentionality. Original dependencies and all standing controls remain unchanged.