Description
Why this matters: Non-coupon attribution path (~40% share) may rely on Shopify fields that are at risk of deprecation. If this path degrades, referral measurement and merchant trust can drop before we detect it.\n\nScope: Clarify dependency on landing_site vs alternate signals, define detection metrics and alert thresholds, and propose mitigation options with sequencing (monitoring-only, fallback enrichment, migration path).\n\nSource signal: projects/referral-team/tickets/2026-04-08-shopify-referral-attribution-recovery.md (revised recommendation #1), projects/referral-team/analysis/2026-04-08-attribution-path-audit.md (open question #2).