Interesting. If you go to the last paragraph of the second page which continues on to the top paragraph of the third page, it says that if the batteries were to discharge and you were unable to use the headset (and not just lose ANR functionality) then it would not be an approved headset.

The QC15 and UFlyMike then would not be an approved combination. The QC25 and the new UFlyMike (when it comes out) seems that it would be approved as the QC25 allows audio with dead batteries. This is, of course, assuming the UFlyMike when released works this way with ATC as well.