These digests are 'template based', so you can update them to your liking. 

To edit the digest template in short and update that string, do the following:

1. Log in to the smg webinterface as administrative user.

2. Got to the menu 'System Management > Templates'

3. In the right panel, you should see various templates in use by your system.

Extend the Digest-one, and click on the download-symbol left to the current-filename of your used digest.

4. This will download you a PHP-template which is used for the digest.

5. When opening that file in your favorite editor, you can search for the '2020' number.

In the default-template this string is around line 487.

6. After saving the file and keeping its original formating and encoding, we re-upload the file to the smg webinterface.

7. After re-applying the new template using choose file... in the webinterface, and applying the changes, the digest-should be updated.

To try this out, you can either wait for your next digest release, or do a manual digest release utilizing the quarantine-settings. 

Also interested in learning more about this subject Can somebody tell me how to update this?