Hi @carl,
Given the board has only recently been put into mass production, I don’t expect there will be major design changes in the near future. If it’s possible to accomplish via a software or firmware change in ArduSub or BlueOS to change / switch the function of an existing port then it may be an option 
I don’t believe it’s something we’re working on internally, but BlueOS is designed to be extensible so that may come about via an external / community effort, particularly once we’ve stabilised the BlueOS API and released the extension system in an accessible form