last season lilly?

ok, i'm in crim law and should be paying attention but instead i'm worrying about what i'm wearing to keeneland in a couple of weeks! so, what do you all think of this outfit? I'm thinking about buying them both off ebay (NWT) - but... is it ok to wear last season lilly to keeneland? also, does anyone have this dress? bc i usually wear a 4 in the more fitted lilly dresses, but i know this one is supposed to fit loosely and i'm considering getting a 6 just to be sure it is not too form fitting.

{and i would just like to note that i do know that "i" is supposed to be capitalized, as well as the beginning of every sentence, but i'm used to typing in Word and it does those two tasks for me! so now i'm just lazy - sorry to anyone whom this bothers :)}