File path for logging cronjobs

I found some information in the forum for the Pro series:
https://community.wd.com/t/guide-how-to-make-persistent-system-changes-crontab-etc/201268
Seems to be valid for the My Cloud Mirror as well at first sight, I also found the /dev/ubi0_0 and xmldbc also has the list of cronjobs.
I’ll work my way through the other thread…