On the Wong et al layout, the Arduinos are all externally accessible if you want to make changes to the code. This is rarely done, but helpful if you want to change the way in which the microcontrollers execute commands (e.g. change the thermostat controller, or the types of parameters for new pump events).
If I want to change the Arduino code on the motherboard Arduinos on the Fynchbio design, I can open the lid and access those. What about the fluidics module, is there an easy way to get in (via port or via RS485), or do I have to unscrew the casing to get in there?