I was told by my local Post Office that if I didn't know how the order would arrive (UPS/FEDEX vs USPS), if I put my street address, 1 Main St for example, but put the ZIP+4 for my PO Box, UPS/FEDEX would deliver to my street and USPS would deliver to PO Box because USPS looks to ZIP+4 for definitive address info. So I started to do that.
What I found was that the Alton PO would send it down to the Bay PO, with a note on the front of the envelope saying "Alton Bay ?" and a stamp asking me to inform the sender what my correct address is
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You could try a similar thing with ATT, I guess. Just hope they don't send you anything.