After panning/rotating they get highlighted in blue again so I'm assuming it's just a visual thing and they don't actually get unselected. However when the faces are no longer highlighted in blue reselecting the faces doesn't add to the dialogue's number of selected faces.
So for example if I have 1 face selected like so:
If I pan the camera and that face no longer shows up as blue I still see 1 selected like so:
And after reselecting that face to turn it blue the dialogue still shows 1 selected like so:
