Backup with backup-manager, s3

Good day, I use backup-manager to backup to Amazon S3.

However, the question how to copy backups to a specific folder in bucket'e?
Directive BM_UPLOAD_DESTINATION="folder_name" result does not. Backups are all the same pour at the root bucket'.

and, as a complement, the second question. Suppose you need to back up a specific directory every 15 minutes. But! even if something in the directory has changed, the backup manager creates a single archive for one day:
File /var/archives/hostname-etc.20101113.master.tar.gz already exists, skipping.
Whether it is possible to win somehow?