It is currently setup to loop off the successful send variable from a previous FTP upload task, within the same Job. I even attempted to write out the Uploaded files results to a variable and then write the variable to a text file, and noticed the same issue. However like I said, only when I set it up as a customer or interval trigger.
It's almost like the task variable does not update until the job completed for the current run, unless it is a file trigger. Very strange, and this worked perfectly file in the 6.1.0 version.
I have ran some tests on a local install, only against a list file task, and looping was fine, so I am not sure if it's an FTP glitch, I do plan on setting up a similar job on my local PC to see if I can replicate it.
One thing to note, this has happened before on our test environment, but since we get very little data through it, I did not think much of it, thought just a hiccup, which it does not seem to be.