Two different things being discussed here:Afaik its not a range bump anyway. The awd jsut got uprated and the performance downrated or more to say the 20 inch wheels got downrated. If you put 18 inch wheels on and change them in the menu it goes back up.
What was being discussed:
The range increase from 310 to 325 for LR RWD. This was an energy increase (no change in the constant AFAIK from everyone I have asked, and also shows in EPA test results).
Not being referred to in this context:
The increase to 322 rated miles for 2020 (not a capacity increase, just a constant adjustment, in combination with better software which improved efficiency and also applied to older vehicles and thus provided more range in some circumstances).