Best/Most Efficient Way to Return All or One Based Off Of Type

I am trying to return a collection of one or multiple Notifications back to the front end for display. I've kicked the wall for a while, and have come up with two different yet similar solutions, posted below.

I'm curious if A: one of these is better than the other, or B: there is better more awesome solution out there and I'm too close to the problem to see it.

The Switch/Case Statement:

    var dl = new Notification() { Type = "dl" };
        var m = new Notification() { Type = "m" };
        var t = new Notification() { Type = "t" };
        var bb = new Notification() { Type = "bb" };

        switch (type)
        {
            case "dl":
                dl.Count = _dlRepository.GetNotificationCount(userId);
                return Enumerable.Repeat(dl, 1);
            case "m":
                m.Count = _mRepository.GetNotificationCount(userId);
                return Enumerable.Repeat(m, 1);
            case "t":
                t.Count = _tRepository.GetNotificationCount(userId);
                return Enumerable.Repeat(t, 1);
            case "bb":
                bb.Count = _bbRepository.GetNotificationCount(userId);
                return Enumerable.Repeat(bb, 1);
            default:
                dl.Count = _dlRepository.GetNotificationCount(userId);
                m.Count = _mRepository.GetNotificationCount(userId);
                t.Count = _tRepository.GetNotificationCount(userId);
                bb.Count = _bbRepository.GetNotificationCount(userId);
                var notifications = new List<Notification>();
                notifications.Add(dl);
                notifications.Add(m);
                notifications.Add(t);
                notifications.Add(bb);
                return notifications;
        }

The Ifs:

    var notifications = new List<Notification>();

        if (type == "dl" || type == null)
        {
            notifications.Add(new Notification()
            {
                Type = "dl",
                Count = _dlRepository.GetNotificationCount(userId)
            });
        }
        if (type == "m" || type == null)
        {
            notifications.Add(new Notification()
            {
                Type = "m",
                Count = _mRepository.GetNotificationCount(userId)
            });
        }
        if (type == "t" || type == null)
        {
            notifications.Add(new Notification()
            {
                Type = "t",
                Count = _tRepository.GetNotificationCount(userId)
            });
        }
        if (type == "bb" || type == null)
        {
            notifications.Add(new Notification()
            {
                Type = "bb",
                Count = _bbRepository.GetNotificationCount(userId)
            });
        }

        return notifications;

Any thoughts/opinions are appreciated.