Hook location for setting-changing plug-in

[reismarktq2]

build_options() is defined in includes/adminfunctions.php.

So would I need to change the hook location to get it to run? How would I call it so that it will work from forum home?

As far as I understand the above code, it updates the setting on every pageload when the time has passed ...

It does, but I plan on adding another conditional that only updates the setting if it's currently true (which is easy enough to do). I wanted to make sure it would work without such a limit before I added it.