Adding another data point. Our production app (StoreKit 2, Product.purchase() called directly on device, no purchase controller) hit the same 'Unable to Complete Request' failures at very high rates from July 27, 2026 20:34 UTC to July 28, 2026 about 07:00 UTC. Roughly 95% of purchase attempts failed at the payment sheet: overnight we saw 43 attempts with only 1 completion, versus a stable 25-36% completion rate on every prior day. App Store Connect server reporting confirms the drop, so it was not a client-side telemetry artifact. Observations that match this thread: Nothing changed on our side: same binary throughout, no product or configuration changes, and it recovered on its own with no action from us. Server-side subscription renewals continued normally through the whole window; only interactive purchases failed. Product metadata loaded normally the entire time (no product load failures). Failures spanned all products, all storefronts, and iOS 18.x and 26.5.x devices identically (so not tied to an OS release). A small fraction of attempts (roughly 5-8%) still completed, so intermittent rather than hard-down. We also saw a short burst of the same error on July 26 22:52-23:31 UTC, overlapping Apple's acknowledged App Store In-App Purchases incident that evening; the July 27-28 window itself shows no status page entry. We filed a support case with full details and timestamps: Case ID 20000122298182. If an Apple engineer can correlate the window above server-side, we are happy to provide transaction-level logs.