You asked if the difference between Backup & Mirror was 'deletion of orphans' from Destination (yes - the latter does, the former doesn't)
You then asked (in effect) if Backup & Mirror both version deletions, and I (in effect) replied 'How can they? Backups don't delete anything!'
Thus, a Backup profile will generally only Version changes to files (where the file still exists on Source). It can't Version deletions because there won't be any files deleted on the Destination (at least, not deleted by that Backup profile, which is what counts)
You then asked (in effect) if Backup & Mirror both version deletions, and I (in effect) replied 'How can they? Backups don't delete anything!'
Thus, a Backup profile will generally only Version changes to files (where the file still exists on Source). It can't Version deletions because there won't be any files deleted on the Destination (at least, not deleted by that Backup profile, which is what counts)