{"ops":[{"url":"site.com/100/test"},{"url":"site.com/200/test"}]}
{"ops":[{"url":"site.com/1000/test"},{"url":"site.com/2000/test"}]}
$json = '{"ops":[{"url":"site.com/100/test"},{"url":"site.com/200/test"}]}';
$json = str_replace([100, 200], [1000, 2000], $json);
echo $json;
//{"ops":[{"url":"site.com/1000/test"},{"url":"site.com/2000/test"}]}