I'm trying to purchase the promotion 1.5 yr North America Speed Camera Update. My current subscription expires on July 1, 2017. When I get to the Select Device page, I get the message "Unfortunately, Safety Camera Updates North America - 1.5 years is not supported by this device." I have a GO 600 even though the device listed with the correct Serial number says its a GO 60S. I don't understand why I can't go ahead and purchase the promoted update. Do I have to wait until my speed camera subscription is expired before I can purchase the update? Any help will be appreciated.