For: storefront / checkout developers migrating off pinnareet/villaCoupon or already on VillaCoupon3 who need the latest backwards-compatible schema fields.
Bottom line
- Every legacy endpoint has a 1-1 replacement (field names changed; payloads are not accepted as-is).
- New coupon schema fields are additive with safe defaults — existing VillaCoupon3 clients do not need a breaking release.