public void Foo()
        {
            DateTimeZone zone      = DateTimeZoneProviders.Tzdb["Europe/Astrakhan"];
            DateTimeZone localZone = DateTimeZoneProviders.Tzdb["Europe/Berlin"];

            var activity = ActivityHelper.CreateForTime("Foo", 2019, 5, 1, 10, 0, 60, zone);

            activity.Begin.Hour.Should().Be(10);
            activity.Begin.Day.Should().Be(1);

            var localBegin = activity.Begin.WithZone(localZone);

            localBegin.Hour.Should().Be(8);
        }