Application Update emails going to wrong email

I have a client that has a WP site installed under a subdomain and I keep getting "Application Updates" emails to my main email address, not the client's email.

Example:
Updates are available for the following applications:
1. Plugin "Akismet" on Client (http://subdomain.client.url). Installed version: 3.0.4. Available version: 3.1.

I have sent the client an email asking them to check the email address entered in the admin panel, thinking that maybe it was a typo, and they say the email address is correct.

I checked their wp-config.php file and they have automatic updates turned off.
//--- disable auto upgrade
define( 'AUTOMATIC_UPDATER_DISABLED', true );

Any suggestions on how I can fix this so the Application Update emails will go to my client instead of me?

Thanks,
Jeff