[re.void]

Дано:

[
			  {
				"EventStartDate": "17/10/2008",
				"EventType": "Restricted",
				"Event": "My Forum",
				"SessionStartTime": "18:00",
				"City": "Ryazan",
				"Type": "1on1",
				"RowCount": 0
			  },
			  {
				"EventStartDate": "17/10/2008",
				"EventType": "Restricted",
				"Event": "My Forum",
				"SessionStartTime": "15:10",
				"City": "London",
				"Type": "3on1",
				"RowCount": 1
			  },
			  {
				"EventStartDate": "24/11/2008",
				"EventType": "Conference",
				"Event": "AAA Test Event",
				"SessionStartTime": "15:10",
				"City": "Paris",
				"Type": "Meeting",
				"RowCount": 2
			  },
			  {
				"EventStartDate": "24/11/2008",
				"EventType": "Conference",
				"Event": "AAA Test Event",
				"SessionStartTime": "16:10",
				"City": "Moscow",
				"Type": "Breakfast",
				"RowCount": 3
			  }
			]

Необходимо сгруппировать по датам, названиям, типам ивентов и их сессий.

и тд. Скрипт цикла перебора массива:

var arr2 = [];
      for (var i = 0; i < arr1.length; i++) {
        if (arr2[arr1[i].EventStartDate] && arr2[arr1[i].EventStartDate].EventStartDate) {
            for (n in arr1[i]) {
                if (n != 'EventStartDate') {
                    arr2[arr1[i].EventStartDate][n] = (arr2[arr1[i].EventStartDate][n]) ? arr2[arr1[i].EventStartDate][n] + ";" + arr1[i][n] : arr1[i][n];
                }
            }
        } else {
            arr2[arr1[i].EventStartDate] = arr1[i];
        }

    }
    console.log('result', arr2);

Прошу помочь разобраться как переработать такой массив.
UPD: необходимый результат HTML

<div class="cib-day-elem">
    <div class="cib-label-am">
        <div type="text" class="event" name="dc_input0" id="dc_input0"><a class="cib-date">"EventStartDate(17/10/2008)"</a><br>
            <div class="cib-event"><a class="typeevent">"EventType"</a><a class="nevent">▶"Event"</a><br>
                <div class="cib-s1"><a class="tm">"SessionStartTime"</a><a>"City"</a><a class="type">"Type"</a></div>
                <div class="cib-s2"><a class="tm">"SessionStartTime"</a><a>"City"</a><a class="type">"Type"</a></div>
                <div class="cib-s3"><a class="tm">"SessionStartTime"</a><a>"City"</a><a class="type">"Type"</a></div>
             </div>
            </div>
        </div>
    </div>
    <div class="cib-label-am">
        <div type="text" class="event" name="dc_input2" id="dc_input2"><a class="cib-date">"EventStartDate(24/11/2008)"</a><br>
            <div class="cib-event"><a class="typeevent">"EventType"</a><a class="nevent">▶"Event"</a><br>
                  <div class="cib-s1"><a class="tm">"SessionStartTime"</a><a>"City"</a><a class="type">"Type"</a></div>
                  <div class="cib-s2"><a class="tm">"SessionStartTime"</a><a>"City"</a><a class="type">"Type"</a> </div>
                </div>
            </div>
        </div>
    </div>