Friends on AT&T have been telling me that when I send multiple-part texts from my Verizon phone, they do not receive the entire thing. I am aware that AT&T does not perform SMS concatenation on inbound Verizon (CDMA) texts; the problem is that chunks of the message are disappearing outright. It would be fine if those occasional 400-500 character texts were received as multi-part messages as expected. I'm on an iPhone 5, currently 6.1.4, was 6.1.3 for past however long it was since 6.1.3 was released. Was jailbroken on 6.1.2 briefly but restored to stock 6.1.2 firmware. I was told by one person that this has been an issue since I switched from AT&T to Verizon months ago but occurs intermittently. Have hard reset my phone already. All I can think to try is an iTunes restore -> set up as new phone. Don't know if calling Verizon would help. Anything else I could try first?