As it stands Virtualmin can schedule backups and keep files for a period of time. I would like to be able to do the following (for example):
Keep nightly backups for 14 days keep the oldest backup for 1 month
if the file is older than 14 days
if there exists a file older than 14 days
dont delete it
If file is older than 28 days
This type of scheduling is probably possible by writing a script to run (either before or after the backup) that says; If the file in the archive folder is older than 30 day, overwrite it with the oldest file in the backup folder.
Whatever solution would work best, but archival backups are important.