MY AWD SR will be made in
MY AWD SR will be made in Fremont, not Texas.
GigaTexas production line is constructed to build a MY chassis around the structural battery pack, not the 'backup plan' non-structural 2170 pack.
Fremont's assembly line, on the other hand, IS constructed around making chassis using 2170 packs.
It's entirely possible the MY AWD SR will be using 2170 cells. But Elon wants to make a lower cost vehicle for both market share and profits this year.
LFP gets him there quicker.