I believe it inherits the same pruning behavior of Borg itself. I don't know the architecture of Borg storage too closely, but I assume that since it is all en

I believe it inherits the same pruning behavior of Borg itself. I don't know the architecture of Borg storage too closely, but I assume that since it is all end-to-end encrypted, Borgbase cannot do the pruning for you. If you use append-only keys, they can't (destructively) prune, you have to use regular keys to do that.