For some reason, some people are having rebooting problems and others are not. You have to look at it like a food-borne outbreak. In other words, why did some people get sick at the wedding reception and others didn't. And then after interviews, questionnaires, and a process of elimination, you can hopefully isolate it to the chicken salad.
It seems to affect people regardless of IPv6.
My iOS 7 thought is probably a billion to one, but I was just attempting to share the kind of logic that is probably needed to isolate the issue as to why some people random reboot and others don't. I'm sure y'all will figure out if it's the chicken salad or the broccoli casserole causing the problem.
If someone developed a questionnaire, and posted it, I'm sure the problem could be isolated/identified/ resolved a lot quicker.
E.g.
1. ISP
2. Serial number of router (date of purchase) component change?
3. WAN type
4. And a whole bunch of other possibilities that could possibly cause a router to random reboot.