Yes Lukas, it is with 2.0.3484.9 - we are very happy so far, and trying to close down our beta, but have found this single issue (as described - when there are a large number of uncompressed files to upload after some time without being able to connect).
I initially thought this was due to one of our timeouts misfiring, as we have one at 60minutes, but I have repeatedly tested through that one several times now and am confident it is not the culprit.
I can find no session timeouts or limits on the (globalscape) server.