Are you nuts!!!
I don't think he will have any problem at all. First, he has had 3 weeks now in between races to jump in a car. second, he knows the cars,because he has been in the paddock most of the year being a kind of teacher to Massa.
How many world titles did he win, Over how many years, and how many different cars.
Yes the rules are different, but they changed while he drove and he still won.
The person and team that should be worried is Macleran. Hamilton can't be at all happy about this.Just when he climbs out of his hole, this happens.
Should be great fun.