Ah! At the top left? Those are A/B terminals to provide an unfiltered data extension - originally for the Data Extension Kit. As I said, normal phone extensions that are connected to the NTE5A stay connected to it. No reconnecting like you had to do with a normal ADSLx filtered faceplate.

My friend has just informed me she has managed to cancelled the order for Infinity. As suggested here, as an Infinity customer at her previous property, she was offered again now it's become available at her new place. When she asked me for help, it seemed they would not let her cancel, but now they have!