- var_export: documentation ( source)
- preg_replace: documentation ( source)
<?php
$tests = [
'abc-def/something/else/',
'abc-def-2019/something/else/',
'abc-def-2019-2020/something/else/',
'abc-def-125-2019/something/else/'
];
var_export(
preg_replace('~^(?:[a-z\d]+-?)*?(?:/|(?=20\d{2}-?){1,2})~', '', $tests)
);