Yes, once the connection is established you can read/write with no problem. On my end the PLC needs to communicate with 2 boilers, each boiler has 3 separate PAC (Master, Gas, Oil) each has their own IP. This make a total of 6 PAC and a total of 30 sec delay cycle 5 sec on each controller.
When you reach out to the development team, perhaps they should mix it up with the server and client sockets, support 3 Modbus Slave and 2 Modbus Master.