When I turned 70 I had to renew my driving licence – this repeats every 3 years.
Essentially you have to declare you are fit to drive – the emphasis being on you to declare any medical condition that might make you unfit to drive.
So if you have an accident and you haven’t declared any reasons you shouldn’t be driving – your in trouble.
As far as I know if there are any grey areas then you should get yourself assessed.
Not heard of any upcoming agreed changes to this.