Well, you'd want to let people know that that's the case, that all polling stations are open for this particular advance poll. On some voting days only certain polls are open. On one of the advance poll days, all the stations are open. Presumably, that would be the information that one is required to state. I guess you could word it differently, but I don't think it's actually a redundancy per se. If you took this out, you'd have to put it in the law in some other form, I suspect.
On November 15th, 2007. See this statement in context.