You do know that the automated cars (and many cars today) read the roadsigns and don't go from a standard database of speed limits. But you raise a good general point regarding the law when in Level 4+ automated mode. This will need defining.
Any views on this mechanism of insulating conservatory roof? Have been looking at replacement roof but perhaps this may be more economical? What are the disadvantages?
https://www.insul-8.co.uk/