If one has an older gen 1 v4.x firmware version My Cloud they could, unofficially, use another OS which may provide one the ability to script their own custom backup of the My Cloud to another device.
https://community.wd.com/t/clean-os-debian-openmediavault-and-other-firmwares/93714
For the newer gen 2 v2.x firmware My Cloud its much harder.
So long as rsync is available via SSH one could possibly script a backup process using (I assume) cron. An alternative to Safepoint is discussed in the following thread:
https://community.wd.com/t/alternative-to-safepoint-reposted/140685
And one might be able to use Goodsync to do some sort of scheduled backup as well.
https://community.wd.com/t/app-goodsync-for-wd-my-cloud-backup-and-file-synchronization/173984
