How to retrieve texts sent to me when iphone wasn't working and did not transfer to new iphone?

Carriers will typically hold an SMS/MMS message for just 48-72 hours. If undelivered in that time, the message is simply purged. There are 20+ billion SMS messages per day world wide so carriers do not hold them for very long if they cannot be delivered. They dump them from their servers.

Apple has no documentation on how long undelivered iMessages are held. Some tech news reports have indicated it may be as long as 30 days, but others indicate it may be as short a week or less.

Where did you find that information? AT&T’s developer documents for their SMS API says 72 hours (although this may nit be the latest document) -> https://developer.att.com/sms/support/sms-api-faqs

“What happens when the phone is switched off when I send an SMS message?

The message is queued and retried for delivery in periodic intervals for up to 72 hours. Once the maximum period of 72 hours is reached, the message is expired and deleted from the retry queue. If the application has registered an SMS delivery notification callback URI, a final delivery notification status will be sent to that endpoint in near real time. The value of the delivery notification status will be “DeliveredToTerminal” if the message is successfully delivered to the handset and “DeliveryImpossible” if the message has expired after 72 hours without successful delivery to the handset.”

Texts are real time communications. They are not stored, other than for a few hours to allow for a device that is temporarily offline.

Texts are queued for a short time (a couple of days, usually), then, if they can’t be delivered they are deleted. The sender should get a notification that the message wasn’t delivered, however.

At the time of transferring data, did those texts exist on the old iPhone? Please explain the, “when iPhone wasn’t working” part. Thanks.

Axel F.