Revealing mistake: In the first scene, when the camera pans back, in the upper left corner of the screen you can see that a part of the tent has been removed to make room for the camera. (00:02:15)
Continuity mistake: When Potter is on the phone, he turns to hush Hawkeye and BJ. As he does so, he's holding the receiver with his left hand, and covering the mouthpiece with his right. He then puts his left hand down on the arm of the chair. When the camera cuts in for a close up, his left hand is on the phone again.
Answer: It is actually Cencompac for Central Command of the Pacific. It is like the headquarters for all military activity in the Pacific Region (Japan, Korea, Okinawa, etc. The newer version of that is United States Pacific Command (USPACOM).
EMTurbo
And the abbreviations were used mainly by the Navy. Especially CENCOMPAC.
Https://en.wikipedia.org/wiki/United_States_Indo-Pacific_Command.