[Unit]
Description=Auto Update System Timer For Universal Blue
Wants=network-online.target

[Timer]
# Run daily at 4:00 AM
OnCalendar=*-*-* 04:00:00

# If the system was off/suspended at 4:00 AM, trigger immediately on resume/boot
Persistent=true

# Wait up to 15 minutes after triggering and Spreads the load on update servers (thundering herd protection).
RandomizedDelaySec=15m

[Install]
WantedBy=timers.target