With release 6.0 of Synology DSM there is a new backup-tool, called "Hyper Backup". It can be used to schedule backup-tasks to different cloud-targets. Especially when the first, initial-backup of one source is uploaded, this might take several days, depending on file size and upload rate. Too bad, if your connection resets during the upload  due to ISP behavior or technical problems: The backup gets stuck. But there is a workaround for that case.