To reproduce:
1. Open attached project
2. Open TouchTest scene
3. Include the current scene in the build - build and run
4. Press the top left corner of the screen while in landscape mode - note the 3rd row of coordinates. The values should be (-,+,+) (x is negative, others are positive
5. Turn the device 180 degrees into the other landscape mode
6. Press the top left corner (where the label is) - the coordinates are now (+, -, +) (y is negative)

If you enable the camera that's under GameObject InputCamera and repeat the whole process the coordinate results would be the same for both orientations.

Explanation:
The camera is not supposed to be functional when it's disabled. You would observe the same thing if you were to say, change screen resolution or some other parameter.