The time taken and status columns in the logs have sense once a scheduled backup has been executed, no before it. They will show the time used to make the scheduled backup and its final status.
As I see in your post above, I suppose that you've defined to execute you scheduled backups every Friday at 07:15 and Moodle has calculated its next backup to be executed next Friday (30th July). Perhaps you've defined it after today's 07:15?
Anyway your Moodle's cron system has to be running to allow scheduled backups to be executed...