Details of oc_activity table maintenance

Nextcloud version (eg, 20.0.5): 27.1.1
Operating system and version (eg, Ubuntu 20.04): Debian 12
Apache or nginx version (eg, Apache 2.4.25): nginx 1.25.2
PHP version (eg, 7.4): 8.2

Given the following text from the admin manual:

There is also a configuration option activity_expire_days available in your config.php (See Activity app) which allows you to clean-up older activities from the database.

Can someone give details about how/when (cron?) the cleanup is triggered?
It does work for me but I would like to understand the details. I have the cron running every 5 minutes but I observed the table being cleaned only once a day without finding anything in the logs.

Thank you,