Thanks for the quick reply !
The copn results look good (see below). The response is more troubling because the 310260 MCC/MNC is presented as two different alphanumeric network codes (AT&T and T-Mobile).
(3,“AT&T”,“AT&T”,“310260”,8) <<< This is wrong. This should say T-Mobile.
(3,“T-Mobile”,“T-Mobile”,“310260”,0) <<< This is correct
I checked a BG95M3 and a BG95M1 and the at+copn output appears to be correct: