I was almost embarrassed to post that simple minded solution. So thanks for posting that one. I am prone to forget that sometimes, stupidly simple is best.
PS to OP. You might need to fiddle with /etc/sudoers in order that cron can be allowed to reboot the machine.
PS to OP. You might need to fiddle with /etc/sudoers in order that cron can be allowed to reboot the machine.