URGENT; Combo Box; change list to new FY

[rob_sheeds]

The combo box I have still lists only FY12 Months. I need it to move the FY13.
Code of the UserForm is this.....

Private Sub cmdProcess_Click()
monthIndex = cboMonth.ListIndex
selectedMonth = Chr(cboMonth.ListIndex + 68)
selectedMonthText = cboMonth.Text
isEMOHasRoyalty = chkEMO.Value
isMROHasRoyalty = chkMRO.Value
isPAJHasRoyalty = chkPAJ.Value
isCRAHasRoyalty = chkCRA.Value
Unload UserForm1
End Sub

Private Sub UserForm_Activate()
Dim wk As Worksheet
Dim a As Long
Set wk = ActiveWorkbook.Worksheets("EDNA MAY")

cboMonth.Clear
For a = 4 To 15
cboMonth.AddItem Format(wk.Cells(1, a).Value, "MMM-YY")
Next a
cboMonth.ListIndex = 0
Set wk = Nothing
End Sub


I am very lost and this is urgent. THANKS IN ADVANCE!!!