Hide Genesis upgrade notice from new site registration login


I’m using a mu-plugin from this post to hide the Genesis upgrade notice


This works well when users login in from here


They land on their dashboard & see the welcome message I set up using the Ultimate Branding plugin.

However, when someone has just successfully registered a new site, they see the screen that states they’ll be receiving an email and it shows their login details, username & admin url. When they click on the admin link provided which is


They are directed to the following where they see information about the version of Genesis


Is there something that can be done so that when someone clicks on the link after they’ve signed up for a new site they are directed to http://mainsite.com/subsite/wp-admin/index.php?

Thank you!