It looks like the only list that shows "created July 2010" is your General Interest List. We do create a General Interest list for any new account on Constant Contact to give them a list to put their contacts in. It looks like the dates of contacts added to this list range from 2010 to 2015. If you select View All Lists on the left side of your contacts page you will better be able to see which lists were added on what date.
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