title: Woocommerce - change shipping cost via hooks (functions.php)
body: <p>I'm using Woocommerce Subscriptions with Memberships and I would like to apply some discounts on the shipping cost according to the membership plan my user have. For example, silver members have a discount of -30% of all shipping method.
  To check the current membership plan i use : </p>
  
  <pre><code>$user_id = get_current_user_id();// Get current user ID
  
  if ( wc_memberships_is_user_active_member( $user_id, 'silver' ) ) {
      //echo 'This is a special message only for Silver members!';
  } else {
      //echo 'I\'m sorry, you are not a silver member. There\'s nothing here for you!';
  }
  </code></pre>
  
  <p>But I don't find any way to change the shipping cost with functions..</p>
  
  <p>Is it possible ? Thanks</p>