I am seeing different StoreKit storefronts and localized prices between a direct Xcode installation and TestFlight on the same iPhone. Environment: App: CountAdd iPhone 15 Pro In-App Purchases: non-consumable App Store Connect base country/region for IAP pricing: Japan (JPY) Japan is enabled for app and IAP availability Results on the same device with the same app code: Xcode Debug: Storefront: JPN Prices: JPY Xcode Release: Storefront: JPN Prices: JPY (¥250 / ¥1,250 / ¥2,500) TestFlight Build 10: Storefront: USA Prices returned/displayed by StoreKit: USD ($1.99 / $7.99 / $14.99) Using macOS Console with the physical device connected, I confirmed that the TestFlight build logs: Storefront updated to ... countryCode: "USA" For the Xcode Release build, the same device reports: countryCode: "JPN" I also deleted the TestFlight app and reinstalled Build 10 to eliminate local app data as a possible cause. The issue remained: TestFlight returned USA/USD. The Sandbox Apple Account is configured for Japan. In some tests, although the app displays the StoreKit product price in USD, Apple's purchase confirmation sheet displays the price in JPY. I am not manually converting or hardcoding prices. The app displays the localized product price returned by StoreKit. I have already reported this through Feedback Assistant: FB25014147 I also contacted Apple Developer Support: Case 102983767864 Developer Support advised that they cannot investigate technical issues involving Sandbox IAP testing and directed me to Feedback Assistant. My main questions are: Is it expected or a known issue for a TestFlight/Sandbox build to receive a USA storefront and USD product metadata while a direct Xcode build on the same device receives JPN/JPY? More importantly, can this TestFlight/Sandbox behavior affect the production App Store version? When a user in Japan installs the production app from the App Store, should StoreKit return the Japanese storefront and JPY localized prices? I am trying to determine whether it is safe to submit/release the app without implementing any manual currency conversion or hardcoded pricing.