Let buyer beware of any ATT credits for switching from another phone or TV plan. I switched 2 lines from Sprint last February with written promise of $600 credit for being U Verse customer. I've made many trips back to this office manager and over 15 calls to customer care. I get lip service they will "escalate" to some unnamed authority and then no phone call back.
ATT sales people are nice but apparently make false promises to meet quotas. Then administration reneges on the offer.