Comment 19 for bug 1227520

Yeah, AFAIK it gets copied according to the transition flag the first time it shows up. Quote from IRC:

24/09 15:42:51 <stgraber> so any file (or directory) listed in writable-paths will be copied to /userdata and bind-mounted on first boot, if the content changes in the rootfs after that, you won't see it until you do a factory reset (which will trigger another copy from the rootfs to /userdata)

Not sure what you mean by /etc/writable/zoneinfo though - a typo?

I think you need to care for /etc/timezone and maybe also /etc/adjtime too.

And the code changes required in timedated too, of course.