Install mega-sync :
wget https://mega.nz/linux/repo/Raspbian_11/armhf/megacmd_1.6.3-1.1_armhf.deb && sudo apt install "$PWD/megacmd_1.6.3-1.1_armhf.deb"

Automation
Full:
sudo sh bkup_rpimage/bkup_rpimage.sh start -c /mnt/sda1/pibackup-$(date +%Y-%m-%d).img
sudo pishrink.sh /mnt/sda1/pibackup-$(date +%Y-%m-%d).img
mega-ls
sudo cp /mnt/sda1/pibackup-$(date +%Y-%m-%d).img /mnt/sda1/backup
sudo rm /mnt/sda1/pibackup-$(date +%Y-%m-%d).img
mega-rm -r -f /backup/pibackup-$(date -d "7 days ago" +%Y-%m-%d).img
Lite :
sudo sh bkup_rpimage/bkup_rpimage.sh start -c /mnt/sda1/pibackup.img
sudo pishrink.sh /mnt/sda1/pibackup.img
mega-ls
sudo cp /mnt/sda1/pibackup.img /mnt/sdb/backup
sudo rm /mnt/sda1/pibackup.img