hey, well done first of all I'm really proud of you for those grades.
It usually depends on the school however if you got really high As they shoudl be predicting u A* however it doesn't really matter if you get predicted A*A*A* or A*AA as long as the uni ur applying to fits the criteria,
take KCL as an exmaple they want A*AA, so if u got predicted A*A*A* or A*AA they would not care or see a difference within them. so don't be too stressed, be proud of ur grades and relax !