Called and got "you have reached an authorized dealer for ATT, please hold." I recently opened an iPhone account and I suspect it is a customer service follow up, but didn't hold to find out.
Calls every morning around 8:30am, 12:30pm, 6:00pm, and 7:00pm. Mostly says "Private Caller," and/or "West" on the ID. Possible that it's a debt collection company.