Data Sorting to a Specific Format

The code below sorts data for me but I will need a modification so as to achieve my new goal.
From the attached spreadsheet, the first tab called “data” is the data that I want to sort in a particular format. The second tab called “Results” is what I sorted already with the old code, while the third tab “Preferred” is the actual thing that I need.
This is what I need:
Whenever the macro meets a cell that has no value in it, it should replace the blank cell with “1*” also whenever the macro meets a cell that has the same date (as you can see that the orange cells have the same date as the gray rows), instead of outputting the result as shown in “Results” tab, I want the macro to combine these rows as shown in the “preferred” tab.
Also you can see that the yellow cell has the same date as “1-Feb-07” I will like to combine it as shown in the preferred tab.
Thanks a lot for your help.
Below is my code:

Sub test1()
    Dim a, i&, n&, m&, arr, j&
    j = 0
    m = Range("A" & Rows.Count).End(xlUp).Row

    With Range("A2", Range("A" & Rows.Count).End(xlUp)).Resize(m * 7, 30)
        a = .Value

        For i = 1 To UBound(a, 1)
            If a(i, 1) = "" Then GoTo oops
            n = n + 1
            a(i + j, 14) = "DATES"
            arr = Split(a(i, 5), "/")
            If Len(arr(1)) = 1 Then
                a(i + 1 + j, 14) = "'0" & arr(1) & "  " & UCase(MonthName(arr(0), True)) & "  " & arr(2) & "  /"
            Else
                a(i + 1 + j, 14) = "'" & arr(1) & "  " & UCase(MonthName(arr(0), True)) & "  " & arr(2) & "  /"
            End If
            a(i + 2 + j, 14) = "'/"
            a(i + 3 + j, 14) = a(i, 2)
            a(i + 4 + j, 14) = "    " & a(i, 1)
            a(i + 4 + j, 15) = a(i, 3)
            a(i + 4 + j, 15) = a(i, 3)
            a(i + 4 + j, 16) = a(i, 4)
            a(i + 4 + j, 17) = a(i, 6)
            a(i + 4 + j, 18) = a(i, 7)
            a(i + 4 + j, 19) = a(i, 8)
            a(i + 4 + j, 20) = a(i, 9)
            a(i + 4 + j, 21) = a(i, 10)
            a(i + 4 + j, 22) = a(i, 11)
            a(i + 4 + j, 23) = a(i, 12)
            a(i + 4 + j, 24) = "'/"
            a(i + 5 + j, 14) = "'/"
            
            If a(i, 6) = "" Then a(i + 4 + j, 17) = "'1*"
            If a(i, 7) = "" Then a(i + 4 + j, 18) = "'1*"
            If a(i, 8) = "" Then a(i + 4 + j, 19) = "'1*"
            If a(i, 9) = "" Then a(i + 4 + j, 20) = "'1*"
            If a(i, 10) = "" Then a(i + 4 + j, 21) = "'1*"
            If a(i, 11) = "" Then a(i + 4 + j, 22) = "'1*"
            If a(i, 12) = "" Then a(i + 4 + j, 23) = "'1*"
            
            j = j + 6

        Next
oops:
        .Value = a
        Columns("N:Y").Select
        Selection.Cut
        Sheets("Results").Select
        Range("A1").Select
        ActiveSheet.Paste
        Columns("B:K").HorizontalAlignment = xlCenter
        Range("A1").Select
    End With
End Sub