After the aggressiveness of the current administration, you think there is a chance the next administration might come along and say "nope, they need to serve the full 35 years".

The sentence is 35 years. They could legally be forced to serve the full 35 for any reason. As far as I am concerned that is the weight being hung around their neck, not the imaginary eight.

And eight years in prison is an insanely long time, don't forget the terrible health care and dangers from other inmates. You can lose all your teeth and die from infections very easily if someone decides to just let you rot.