I'm starting to look for a pre-owned 2016 or 2017 4 or 5 series BMW. My wife has as 2013 Audi with 3G/2G. Audi changed hardware and firmware in 2017. Anything before will go stupid as soon as 3G/2G becomes NLA (imminently). I don't want to suffer that fate for at least a few years in a newer BMW. What cellular network carrier(s) and service (4G etc) is used in 2017-2018 years in BMW 4 & 5ers for online Nav destinations and traffic data? I can't find a definitive answer.