Amazon is not giving this option anymore for regular customers, I think that you have to be a prime member to receive the Two-Day Shipping for "free", otherwise you have to pay like $8 if you want to receive it on release date. :(
You should probably get a email soon. I pre-ordered another game and a couple of days later I got an email saying my order had been upgraded to have free-release date delivery. I'm a prime member and when I go to pre-order they don't even list "release date" in our options. I think M.G.M is right and they may be reserving that for members only. I'm not sure though.
As for the two day shipping , it probably will be there by release date though. Since it comes out on a Tuesday they may ship that Friday or Saturday before. Two day shipping is pretty quick that's why I joined Prime in the first place.