You might have noticed I send another email with some files as additional information.
I write for I have another clue that will make it possible for you to reproduce. (I already mentioned an empty source folder.)
It happens while procession many sessions in a Project. The problems appears when a session encounters an empty source folder. The source folder might be really empty, or it appears empty to Synchonize It! due to set criteria. For instance the criteria “Not older than” might mean that no valid files appear in the source folder.
Now what seems to happen to me, you should check this!, is that Synchonize It! realises it has nothing to do here and continues with the next sessions in the project. The problem is (I think): it does not (never?) update the target Package file name, as it should, getting at work with the next session . It keeps the target Package file name from the session in which he stumbled on an empty source folder and starts processing in this Package, mixing sessions and files into this one
I think I hit it, or at least I got very close to it. And this can be easy checked. Please, can you fix it?