There was an initial report that suggested that Samsung would remotely deactivate unreturned handsets (which later turned out to be false), but now according to a report from AP, it seems that Samsung will deal with unreturned handsets through a software update that will see Note 7 handsets have their batteries limited to a maximum of 60%.
What this means is that if you don’t return your Note 7 in exchange for the replacement unit, a software update will prevent you from recharging your phone to more than 60%. According to Samsung, “It is a measure to put consumer safety first but we apologize for causing inconvenience.”
However it should be noted that this is what Samsung plans to do for the South Korean market. It is unclear if Samsung will institute this plan in other parts of the world, but it does sound like a potential plan, although we guess whether or not users will actually bother updating is a different story.