<?php
/*
INSTRUCTIONS FOR THIS CODE:
On your RSS URL in Mailchimp add &allow_mailchimp=true to the end of it.
Then copy the below code and paste it into a plugin like My Custom Functions or Code Snippets on your site.
This will allow MailChimp through the content blocks.
*/

function allow_mc_through($block, $post, $uri) {
  if(isset($_GET['allow_mailchimp'])) {
    $block = false;
  }
  return $block;
}
add_filter('mepr-pre-run-rule-content', 'allow_mc_through', 11, 3);