BmuS is designed to be run via cron. You don’t need to keep a terminal window open.
To run the backup every night at 03:00 AM, open your crontab (crontab -e or sudo crontab -e) and add:
Bash
0 3 * * * sudo /home/pi/bmus.sh > /dev/null 2>&1
Note: I recommend running it as sudo (root) to ensure it has permission to read all system files and mount drives.