They might or might not be constructing something but as far as the thing word bufferzone implies, that's not really possible in most areas.
1) There are villages immediately next to the fence. No way Pakistan is investing that much time and energy to ethnically cleansing across a wide stretch
2) moving positions forwards in most areas only means moving down into a valley since the border mostly runs along ridges and peaks. Putting you in worse position.
The only thing I can think of that can be called a bufferzone are area denial attempts. Like, Mines along the fence, in sensitive areas, is a reasonable thing to expect.
Coordinates of the Turkamanzai camp 33°36'59"N 70°11'48"E
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