No, backup schedules cannot be changed. Once you enable backups for a Droplet, we automatically assign it a backup schedule that can’t be altered. However, you can backup your Droplet at anytime using snapshots and can automate the taking of snapshots using a script that interacts with the DigitalOcean API.
Snapshots create an image of the Droplet the same way a backup does, but snapshots persist on your account even if the Droplet is destroyed. You can create a new Droplet from a snapshot at anytime.