Testing version: 2.0 (11657) on iPhone and iPad
What were you doing: Trying to expand the time to lock my encrypted notes.
What feature did you use: Protected/encrypted notes in settings.
What happened: The chosen time always returns to “immediately”
As far as I know there has never been any option to lock after a period of time. The “lock” button is always immediate because the notes will auto lock when bear has been “slept” in the background.
In 2.0 (11657) on iPhone, there’s an option under Settings > Privacy to set “Auto-lock notes after” time:
In my case, it’s currently set to “2 minutes” with options ranging from “Immediately” up to “1 hour”, but, similar to @thomas28, I’m unable to change the value. To be precise, I can choose any of the available settings, but when I leave & return to the privacy setting it always shows “2 minutes” again. So, it looks like @thomas28 is stuck with “Immediately” and I’m stuck with “2 minutes” for this setting until an update to iOS fixes the bug and allows changes to this setting to be persisted. 
