Okay you're right; the sentence is a bit tricky. However it does not say you may not use a signature that has been used as an entry before. If you read it again, you should notice that all it says is that you may not use a signature not being made 'in the week following', which she clearly has. I'm not going to argue with you about this because I really don't care and because we only have like 2 participants anyways, we'll just disregard the rule in this case, for this sotw.