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It was my 3 most common and recent. Last time it was one common and two random. I really don't know at this point.
 
I've got one person I've texted once about an hit after I got the phone, one from yesterday and then my wife. There are 16 conversations above the one from launch day.... It also doesn't recommend group conversations. I did create a new message from it just now and it updated, but still not any pattern that I can see. Hmmm.
 
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