@safetymatters
You'll need to update function for class-twitter.php. Which is located here on your sites server wp-content>plugins>wordpress-seo>front-end>class-twitter.php
Just swap out the code in this section
/**
* Displays the authors Twitter account.
*/
public function author_twitter() {
if ( isset( $this->options['twitter_site'] ) )
echo '<meta name="twitter:creator" content="@' . trim( $this->options['twitter_site'] ) . '"/>' . "\n";
}Good luck!
Rob