It has been explained to you here and I would be VERY surprised if the next step in the appeals process wasn't fully explained within the decision letter you received.
But again the next step is the Board of Review. DES: Board of Review
Thank you, but I don't want to appeal if I don't have to because of an error that THEY made with the date.
I'll try to state it more clearly than above, do I have to file an appeal to correct THEIR error in writing down the date?