Actually, the above is the way forward (if you want to avoid lots of empty 'spam' Dest folders), but you'd need to couple it with a mechanism that can remember files that were previously copied, so that it doesn't copy them again (it will normally propose to copy everything, because when compared to the new (empty) folder it just created for you as requested, everything is 'Source-only', and your rules say to copy all such files).
If you go to the Fast Backup page, and simply enable it ('Perform a Fast Backup') and nothing else, you should find that (after run-1 as a Fast Backup), it doesn't copy stuff it copied before that still has the same properties (i.e, not new or changed). Essentially, you use a sort of Incremental backup, but one that never ends, which (if what you want is a series of dated/timed subfolders containing recent changes since previous run), will give you just that.
You'd still need to use the script (etc) trick to cull the empty/unused dated/timed subfolders on Dest, though. No, there's no way to ask it to scan Source against 'database' and only if changes found to create the new Dest. The Dest gets created (or, is found to exist anyway) before the scan ever happens.
If you go to the Fast Backup page, and simply enable it ('Perform a Fast Backup') and nothing else, you should find that (after run-1 as a Fast Backup), it doesn't copy stuff it copied before that still has the same properties (i.e, not new or changed). Essentially, you use a sort of Incremental backup, but one that never ends, which (if what you want is a series of dated/timed subfolders containing recent changes since previous run), will give you just that.
You'd still need to use the script (etc) trick to cull the empty/unused dated/timed subfolders on Dest, though. No, there's no way to ask it to scan Source against 'database' and only if changes found to create the new Dest. The Dest gets created (or, is found to exist anyway) before the scan ever happens.