I am using iOS 10.1.1 and iPhone 7 Plus 128 GB. My Phone has the dreaded Intel Modem. I have noticed that whenever I go in a area that has no 4G coverage like inside building, it drops to 2G or Edge network. But once I come out of the building, the phone stays on 2G mode for long time which seems like forever. I have to switch to Airplane mode and back on to force it to connect again to 3G or 4G network. My carrier is Vodafone IN. I have tried it with Airtel IN as well with same results. My previous 6S Plus never had this 2G/3G/4G switching difficulty. Is it iOS or Intel Modem which is at fault? Anyone else facing similar issue?