To fix this in portrait, modify the file
Engine\Build\Android\Java\src\com\epicgames\unreal\GameActivity.java.template
Find the line that looks like this:
int bottomDiff = Math.abs( mainDecorViewRect.bottom - visibleRect.bottom );
Add the following code below it:
// BEGIN Paratus mod
visibleRect.bottom -= visibleRect.top;
// END Paratus mod