Originally Posted by
Denont
From GTAA site: Duty Free Shops are open two hours prior to the scheduled departure of the first flight and close approximately 30 minutes prior to the last departure flight. For additional information, please see Duty Free Shops.

I try calling too but got no live person.
That's very helpful though...somehow I missed that caveat on the GTAA website! Not to mention the fact that I was getting nervous as nobody had answered for a few days - thanks for restoring my FT Faith ;-)