Two physical iPhones on public iOS 27.2 (24B119), using separate adult US Apple Accounts, produce different results from the Declared Age Range framework under a BR country classification.
Device A displays the mandatory Brazil-sharing notice, does not accept Never in the native selector, and returns an 18+ range to a real request with ageGates:18.
Device B accepts Never after the update. The same local checker receives declinedSharing with no age bounds. Never remains checked afterward. The checker invokes requestAgeRange even when regulatory eligibility is false; it does not synthesize a refusal locally. Device logs indicate normal flow, without a sandbox override.
Selected diagnostics show US billing countries for App Store, Music and iCloud on both devices and BR detected on both. Their separate age-assurance classifications differ: BR with account eligibility true on A, versus unset with account eligibility false on B. Unset is not being treated as US. The captures were made on different dates, and identical account histories and management payloads have not been established. Both devices are supervised. No location simulation or network filter was active during B's test.
For developers handling these API results, what documented account or device criterion explains this difference? What supported diagnostic and correction path is available when the native sharing control is unavailable on one device but effective on another under the same detected country?
The detailed comparison has been supplied privately through Feedback Assistant. This question concerns the public framework's behavior and supported remediation; it does not assume US billing country alone creates an exemption.