$re = '/Start Time : (.+)/';
$str = 'Text at the beginning
Alert : Alert DESC
Some other text blah blah
Start Time : 04/17/2023 09:00:00 AM
End Time : 04/17/2023 12:00:00 PM
Other text etc etc';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php