Which Br for america ground?

I am currently playing with america 8.3, have the xm 800t and m3 bradely researched. I wonder if I should go for the 9.3 lineup or head to 9.0? I don't have the AA line researched, I am looking forward to have my A-4 in GRB.

Also, do you guys know what america premium tank will be in the battle pass shop for like a day of use? Like for air it is the AV8A