I’ve not been able to find much out about this, but they do have one at the CfCH in Cambridge. https://www.computinghistory.org.uk/det/36892/BBC-Micro-Red-Box/

I wonder if it used X10? If so it could still be integrated with home assistant.

I would (hate|love) to see one of our setups built with 1980’s tech. Imagine the yellowed white (and red) boxes and bulky everything