After the test " if empty response or bad response, return original ip ", you have to add a test to verify that the last character of the response is a 0 :

// Verify the last character of response is 0
$responseLength = hexdec(bin2hex(substr( $response, $requestsize + 11, 1 )));
if ( bin2hex(substr( $response, $requestsize + $responseLength + 11, 1 )) != '00' ) {
return $ip;
}

if ( empty( $response ) || bin2hex( substr( $response, $requestsize + 2, 2 ) ) != '000c' || bin2hex( substr( $response, $requestsize + 12, 1 ) ) != '02' ) {

return $ip;

}

The step after light speed is shown in nature by black holes. Space-time is faster than light.

Think of creating and using wormholes (minus all the FTL tech we currently use to define them) to "escape" the space-time that is currently lights boundaries as well.

That beyond FTL limit leads to the idea of escaping the universe created by the Big Bang, which leads to the idea that universes themselves may be as numerous as the stars are within them.

Oh to see the breakthrough!