Well they wrote that they can’t promise anything and this doesn’t sound very hopeful …
Aside from limitations in device performance, there are also restrictions on resource usage imposed by Apple and Google which make this scale of data transfer, synchronization, and storage impractical within a mobile app.
We don’t have any next steps with your case, but I’m hopeful our continued work around Arc performance may in the future help eliminate troublesome issues for you.
but if you are lucky, this more recent information might (or not) help: