Snapshot saving multiple backups per day even if it's set to once a day

Hey guys,

the title says it all. I've set up snapshot to run one backup daily and keep 14 of them on my server. As a destination i set up dropbox and for some reason it saves multiple backups per day. I have that issue on 2 of my sites. Others work just fine and i don't see any difference in configuration.

Also, what's the difference between "once daily" and "daily managed snapshot" at the backup interval? There's also an option that says "managed backup processing" - can you clarify what these options stand for?

Thanks!