OpenSuse 42.x Update :
/etc/crontab shows a file /usr/lib/cron/run-crons that is supposed to run every 15 minutes.
/usr/lib/cron/run-crons in turn ( has may lines of code ) which is looking for a variable called DAILY_TIME in /etc/sysconfig/cron
The file shows;
# At which time cron.daily should start. Default is 15 minutes after booting# the system. Example setting would be "14:00".# Due to the fact that cron script runs only every 15 minutes,# it will only run on xx:00, xx:15, xx:30, xx:45, not at the accurate time# you set.DAILY_TIME=""Set it to the time you need and restart cron via;
systemctl restart cron.service