No, UpdraftPlus does not support Amazon Cloud Drive, and we have no plans to support it. Amazon are pitching this as a storage solution for media, particularly photos. They have not made any developer documentation or development toolkits available for arbitrary storage. All their signals are that they wish things like website backups to be stored in S3, for which they have abundant developer support. As such, to try to support Cloud Drive would be trying to fight uphill, and past experiences of supporting storage backends that the vendor was lukewarm about have not been positive. Therefore, we will not be doing it.
Posted in: Other remote storage questions