There's actually no expectation how it will work. As said, to get flight mode working at all, a bug in the security platform is used (exploit, if one could use such a naughty term for a benevolent feature). But in certain conditions the platform fixes the credentials. I do not know what these conditions are, but I suspect installing/uninstalling some other software may cause it.

So the short answer is, yes, reinstall may be only a temporary fix. Real fix is using inception or open mode kernel. And that's probably the only way forward after PR1.3.