Quick look says 6s is 4g compatible? Not sure it'd be that big of a deal? I specifically bought the phone with CDMA support, and it's been working for 2 years now.
Well, "working" as in, it works when I drive far enough from home...
If my 6s loses support I might just quit having a cell phone, there's no real coverage out here, I know friends who just leave theirs off as they don't have coverage at home. I would just have to figure out how to MFA stuff, that's the only thing I "need" my phone for. Maybe I could keep the phone, and just ignore the fact that it has zero usage as a phone...