Maximum Time of Post Delayed

Question

I have this method:

public static Runnable runAtDate(Date date, final TimerCallback callback)
{
    Date now = new Date();
    long timeTo = date.getTime() - now.getTime();

    if (timeTo <= 0)
    {
        if (callback != null)
            callback.onRun();
    }
    else
    {
        final Runnable runnable = new Runnable()
        {
            @Override
            public void run()
            {
                if (callback != null)
                    callback.onRun();
            }
        };

        handler.postDelayed(runnable, timeTo);
        return runnable;
    }

    return null;
}

This works fine when the date is around a few hours later (1, 2, 3) but around 8 hours this method does not work anymore. And since other timers have not been reliable (delayed and whatnot) I chose to use this, because it always execute right on time - when it works.

My question is, what is the maximum hours that a postDelay can run? Do I have to add a new postDelay every (some hours) adding the difference between (some hours) and the exact date?