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<?php

$str = 'J2123409871111222';
preg_match_all('/(.)(\d{4})(\d{4})(\d{4})(\d{4})/', $str, $matches, PREG_SET_ORDER, 0);
print_r($matches);
Success #stdin #stdout 0.02s 23732KB
comments (?)
stdin 
Standard input is empty
stdout 
Array
(
    [0] => Array
        (
            [0] => J2123409871111222
            [1] => J
            [2] => 2123
            [3] => 4098
            [4] => 7111
            [5] => 1222
        )

)
https://ideone.com/Hay4Pa
language:
PHP (php 7.3.5)
created:
7 years ago
visibility:
public

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