So I sold my iPhone 6 this past Saturday and figured I would not be able to use the majority of the features on my Apple Watch until next Friday when my iPhone 6s delivered. However, randomly today when I turned on my AT&T hotspot device. I started receiving iMessages on my Apple Watch. I am even able to reply to messages. Maybe I missed something and forgive me if I did but I am shocked lol. I can confirm the Apple Watch is connected to the hotspot. When I look at the connected devices it is listed. The watch was able to connect I guess by remembering the wifi profile that was on my iPhone 6. Pretty cool.