WI: Elizabeth of Russia lives longer

[Sian]

What would happen if Elizabeth of Russia manages to live a few years longer (say, she takes the medicine prescribed by court doctors) hence delaying Peter III's ascension and blocking his hand in saving Prussia in the Seven Years War?

Prussia is in the ropes with little to no realistic chance of getting out unharmed, but who partitions what, and what would happen afterwards? An intriguing effect could be that Britain bails earlier, hence aren't in such a bad position in terms of economy and war weariness, when the ARW comes knocking

 

[Gwrtheyrn Annwn]

What would happen if Elizabeth of Russia manages to live a few years longer (say, she takes the medicine prescribed by court doctors) hence delaying Peter III's ascension and blocking his hand in saving Prussia in the Seven Years War?

Prussia is in the ropes with little to no realistic chance of getting out unharmed, but who partitions what, and what would happen afterwards? An intriguing effect could be that Britain bails earlier, hence aren't in such a bad position in terms of economy and war weariness, when the ARW comes knocking

Its pretty simple, Prussia will be defeated in the Seven Years' War and Austria was almost certainly regain Silesia. The annihilation of its principal ally will probably make Britain bail, as you say, but I would think that Britain will still gain colonial territory in the Americas where they had supremacy, less territory but Canada would probably still be lost.