Hello jonfd.
Im having the same problem as you. I ordered the phone a week ago and it is still Being Processed. Im also a JUMP customer and ordered at a local store. It is very disappointing as this devices are no cheap and we have to wait all this long. I have also called them many times and they just keep transferring me as they do not have any other explanation an they told me the same thing they told you.
It will be good if they have a way to check your place on the queue on when your Iphone will be shipped or they can update the process status to at least show they are aware of it and working to ship your device but Tmobile does not seems to be very smart. I also notice their representative are just replying with the same answer to all forum posts and not looking deep into these problems.