MySQL log filling up with unwanted "Status information" on server reboot due to ...

This has been plaguing me for a while, so it's time to ask.

The MySQL error_log fills up with "Status information" when the server reboots due to SIGHUP. Here is a link describing the behavior: MySQL Server response to SIGHUP signals

I understand what's going on, but don't know how to fix it.

I have one script that controls the starting/stopping of mysqld: /etc/init.d/mysql

And here is the sourced mysql-helpers file referenced by the init.d script.

I can't find where the SIGHUP is coming from? Or maybe it's coming from the OS? Debian 10.

Edit

Doing service mysql restart or stop never produces the extra log entry, so maybe it has something to do with the shutdown process during server reboot|halt? I don't understand SIGHUP enough to determine if I'm on the right track or not.

If during shutdown your init.d-script is not run, all remaining processes (including mysql) will get a SIGHUP followed by SIGKILL it smells like this is what is happening there.