Initially this method was returning a number of missed schedules, but
that turned out to be not reliable for some complex schedules. For
example, those which are being run only during week days. The second
approach was to only return a boolean indicating the too many missed
information. It turns out that we need to return all three values:
none missed, few missed and many missed, to let consumers know what to
do, but don't leak the wrong number out of mostRecentScheduleTime.
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