I know it's generally advised to apply them manually, but I did find this site with a sample script. I haven't personally used it, so please let us know if it is effective or not. https://www.instructables.com/Keep-your-FreeBSD-system-up-to-date/
That article is just "how do you do upgrades". Looks like target audience is for new users; also the article is 11 years old so a lot would have changed even if they covered the automation.
TIL you can do fetch and install together, I used to do them seperately (and manually) I have a cron job for pkg update && PKG upgrade though.
But the install part of freebsd-update prompts for user intervention. Don't see anything in the man page about automation. Going to setup a VM to play around with this. will report back with findings.
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