kfos

//Change the 'Billing details' checkout label to 'Contact Information'
function wc_billing_field_strings( $translated_text, $text, $domain ) {
switch ( $translated_text ) {
case 'Billing & Shipping' :
$translated_text = __( 'It works!', 'woocommerce' );
break;
}
return $translated_text;
}
add_filter( 'gettext', 'wc_billing_field_strings', 20, 3 );

It worked for me without a space in the amp;