On March 31, 2025, Stripe shipped the Basil API version. Among other changes, it removed three fields from the Subscription object that a lot of production code was reading: current_period_start — moved to subscription items current_period_end — moved to subscription items billing_thresholds — removed entirely (later reintroduced — more on this) If you upgraded your account's default API version without pinning the SDK, the endpoint still returned 200 OK . The subscription objects still serialized cleanly. The fields your code accessed just came back undefined . One of those fields is current_period_end . If your app uses Stripe subscriptions at all, there's a very good chance you read current_period_end somewhere. Maybe it populates the "next bill date" in your UI. Maybe it drives a cron job that reminds customers before renewal. Maybe it gates feature access for annual plans. Whatever it is, it quietly stopped working.…