Apply coupon and remove billing details field

I’m interested in removing some of the billing details fields when a specific coupon is applied to the cart.

I’ve successfully used this code (below), however the fields only change after I refresh the browser page. When the coupon code is applied the “your order” totals are dynamically updated but I can’t get the Billing Details to update.

Is this custom Javascript or can this happen with WC actions?

add_filter( 'woocommerce_checkout_fields' ,'custom_override_checkout_fields' );
function custom_override_checkout_fields( $fields ) {
    global $woocommerce;
    $coupon_id = 'cheeks';

    if (in_array($coupon_id, $woocommerce->cart->get_applied_coupons())) {

        //unset($fields['billing']['billing_first_name']);
        //unset($fields['billing']['billing_last_name']);
        unset($fields['billing']['billing_address_1']);
        unset($fields['billing']['billing_address_2']);
        unset($fields['billing']['billing_city']);
        unset($fields['billing']['billing_postcode']);
        unset($fields['billing']['billing_country']);
        unset($fields['billing']['billing_state']);
        unset($fields['billing']['billing_phone']);
        unset($fields['billing']['billing_company']);
        //unset($fields['billing']['billing_email']);
        unset($fields['order']['order_comments']);
    }

    return $fields;
}