operation,purpose,rule,use_here
Same-side BC subtraction,Measures a distance within BC chronology,Earlier BC label − later BC label,1936 − 1446 = 490
Local Exodus-centered complement,Pairs stated BC coordinates equally distant from 1446 BC,R₁₄₄₆(x) = 2892 − x,1936 ↔ 956; 1876 ↔ 1016; local audit only
Formal repository Mirror target generation,Generates counterpart coordinates in a declared cross-axis state,Appropriate Mirror protocol with single/paired and phase controls,Not activated by the 980-year comparison
Civil BC–AD elapsed span,Measures elapsed time after cross-axis endpoints are specified,BC + AD − 1,Not applied to these BC-only spans