The insurance will be split, for 100% autonomous cars it makes sense for the manufacturer to handle the public liability insurance
Not really..... only, for liability resulting from the manufacturer's negligence. Your autonomous car can still cause an accident and you be responsible for not ensuring that it is properly maintained and inspected, OR you chose to travel under somewhat hazardous conditions such as severe weather under which it is to be understood by you the owner, that are conditions where any driver is less capable and more likely to cause damage, And there is always a certain amount of risk involved which you accept responsibility for by taking that risk.
Also, people tend to keep their vehicles beyond their manufacturer's warranty, after which time, it is no longer promised to be fit for the purpose and free from defects, anyways. It is ultimately the buyer's responsibility to understand what they are putting on the road and to make sure that it is safe to their satisfaction, Because they have to take responsibility for it, OTHERWISE they would have no incentive not to run Autonomous vehicle Version 1.0 that has known defects, without upgrading, and without participating in a manufacturer software module recall on a timely basis.