I took advantage of the iPhone 7 trade in promotion and traded our two iPhone 6 phones for the $650 credits. Once I received mine and my wife's iPhone 7's I sent in our two iPhone 6's on Oct 5 at the same time (two separate packages). On Oct 24 I received an email saying one of my old phones were received and credited. As of today, Nov 4, the second phone I sent in still has not been credited. The online trade-in status still says "Your shipment has arrived" and has not changed for weeks. Why is there a delay with the second phone being credited? I assumed since both were sent in on the same day they would be credited around the same time but it's been 2 weeks since I got credit on the first one.
There is an overwhelming amount of phones being traded in for the iPhone 7 under this promotion. There are only human beings who can work as quickly as they can to process all of the returned devices. If you want to know any further details of your specific case call the provided customer service number. We can't help you here.