FWIW, I agree with Andy and Dan. Your agreement can say anything you want it to - the question is what your agreement says. The language in your poll is different from most that I see, which would read along the lines Dan is talking about. For instance, "Prime Rate, as published in the WSJ." That type of language makes it a little clearer than what you quoted. But even going just by the language you quoted, the WSJ prime cannot change until the WSJ is published (unless you want to specify the online version, which is not - at this point - the normal thing people would think of when you say published in the WSJ).
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