It's lazy but as you have the part 1, you can get part 2 like this:
$part1=$text;
if (preg_match('/^.{1,15}/s', $text, $match))
{
$part1=$match[0];
}
$part2 = str_replace($part1, "", $text);
It removes the part 1 from the string and as a result you'll have part 2
Better solution (but a little bit harder) is to get part 2 index by capturing the offset in preg_match method. It gives you the position of the matching string:
$part1=$text;
if (preg_match('/^.{1,15}/s', $text, $match, PREG_OFFSET_CAPTURE))
{
$part1 = $match[0][0];
$part2 = substr($text, $match[0][1] + strlen($part1), strlen($text) - strlen($part1));
}
The second solution might need some fixes.
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