Thank you very much for the detailed guidance. We're updating our logging as soon as possible to capture and retain the apns-id returned in the APNs response headers, so we can provide it for future cases. However, some of the "not received" cases we're currently investigating occurred before our apns-id logging was in place, so we don't have the apns-id for those. For these earlier cases, would it be possible for you to investigate using only the push token (device token) together with the approximate send time, so we can see the specific error? We do have the tokens and timestamps for those cases. We're also a bit hesitant to post sensitive information such as apns-id, push tokens, or device tokens here on the public forum, out of concern that they could be misused to send unauthorized notifications. Is there a more private channel, for example email or a support request, through which we could share these details securely? Thanks again for your help.