Multi Step Checkout - How to change returning customer message

If you want to change the message that is shown at the frontend in the login step:

put this code in your functions.php:

if( function_exists( 'YITH_Multistep_Checkout' ) && ! function_exists( 'yith_wcms_form_checkout_login_message' ) ){
    add_filter( 'yith_wcms_form_checkout_login_message', 'yith_wcms_form_checkout_login_message' );
    function yith_wcms_form_checkout_login_message( $login_text ){
        return __( 'YOUR NEW TEXT HERE!!!', 'yith-woocommerce-multi-step-checkout-premium' );
    }
}

replacing the text of the example NEW YOUR TEXT HERE !!! with what you want to print.