<?php
$content = <<< LOL
START
A: 567 B:345
C: 345 D:485
START
A: 345 B:267
C: 980 D:054
LOL;
preg_match_all('/(START)\s+(A:\s+\d+\s+B:\d+)\s+(C:\s+\d+\s+D:\d+)/i', $content, $result, PREG_PATTERN_ORDER
);
// your code goes here
PD9waHAKCiRjb250ZW50ID0gPDw8IExPTApTVEFSVApBOiA1NjcgQjozNDUKQzogMzQ1IEQ6NDg1CgoKU1RBUlQKQTogMzQ1IEI6MjY3CkM6IDk4MCBEOjA1NApMT0w7CgpwcmVnX21hdGNoX2FsbCgnLyhTVEFSVClccysoQTpccytcZCtccytCOlxkKylccysoQzpccytcZCtccytEOlxkKykvaScsICRjb250ZW50LCAkcmVzdWx0LCBQUkVHX1BBVFRFUk5fT1JERVIpOwoKcHJpbnRfcigkcmVzdWx0WzFdKTsKcHJpbnRfcigkcmVzdWx0WzJdKTsKcHJpbnRfcigkcmVzdWx0WzNdKTsKLy8geW91ciBjb2RlIGdvZXMgaGVyZQ==