I am so sorry about your problem and hope you can find another Anna.
I'm a little afraid I might have the same situation whenever my doll (not even confident to say she's Anna now) gets here, since she has also been stuck in TN for days and still has not been updated. I've now heard that 5 people have had the exact same scenario happen and am very very nervous.
Out of curiosity, how much did UPS say your Anna-that-turned-out-to-be-Elsa doll weighed? Anna is supposed to be 5.1 pounds, while Elsa is 5.0. I don't know if UPS weighs the dolls themselves or is provided that number by someone else.
Also, did you call Disney Store Guest Services specifically to report the error? I know for a fact they are out of replacement Elsas, but they might have some Annas left. So not only could you potentially get your Anna, but you could also help someone who needs a replacement Elsa for whatever reason.