After a week of waiting for a response to my support ticket I ordered another X1C and put in a return request for this one. The first response to the return request was that it was faster to get a new AP board, but they would allow a return if I wanted. I elected the return, then got a response saying they needed to get approval for that and asking for my invoice (strange, since I’d think they had that). I sent the Bambu invoice, and am now waiting for a return label.
I eventually got a response to my support ticket stating that it’s the AP board and it would need to be replaced, but I’m trying to go the return/re-buy route instead. If it’s not the AP board, or if they send the wrong one, I can see this issue dragging out a long time.
Also @Jrock my printer was using the Bambu power cord plugged directly into the wall outlet (same, 120V/15A), and I didn’t have an SD card in the slot.