Time to Think!!

According to everthing I read, the 2008 Sacagewea could not be minted because of a glitch in the law. Finally the Law was ammended for production. Well I ordered two rolls last week and one has a 4/08 date, but the other has a 1/08 date. Does this mean that the mint produced these coins before authorization. After seeing the 2008 W silver eagle with the 2007 reverse, who is minding the mint?

This brings me to another question - Wasn't the 2006 reverse the same as the 2007 on the silver eagle? Why is the the coin labled 2007 reverse verses someting like "Prior year(s)reverse"?