I have no information about any such limits.
I pinged the team though.
The transfer is happening between your node and destination nodes, the satellite is not involved in data transfers. So, if there are limits, they likely on destination node’s side. Or your router can’t handle the load.
I have had a ticket where operator was unable to exit successful with Mikrotik router. I did not deep into details of the Mikrotik configuration, but when the operator connected their PC directly - the GE was finished in a few hours.
So, I would suggest you to try the same.
Errors was exactly like yours, also - “no route to host”