See what was done in more detail https://unixguru.info/maintenance/
Inline with WordPress, we have switched the default verion of PHP to 7.4.x
There is currently an issue with MySQL/MariaDB, which we are looking at actvely. We will update this new item when we've diagnosed/fixed the issue. The filesystem containing the MySQL database got dismounted, so no databases would function. Trying to restart the database, caused a "new ...
We have replaced SpamAssassin with MailScanner, which is a far superior product and gives more granular control over the blacklisting and whitelisting of domains and email addresses as well as giving the administrators a better understanding of what is happening on the server.
Previously if a person "moved away" a domain, but left it configured, LetsEncrypt would try to renew the SSL certificate every day until the renewal was disabled. We have now changed this, so we warn you that your renewal failed for 5 days, after which we disable the renewal for that domain.