[gr8styl]

Φίλε Γιώργο,
Ο παρακάτω κώδικας κάνει νομίζω αυτό που θέλεις.

Sub Copy_month()
Dim LastCell As Range
  Application.ScreenUpdating = False
  Range("Data").Copy
  With Sheets("Update")
    Set LastCell = .Cells(Range("Months").Row - 1 + _
      Application.WorksheetFunction.Match(Range("A1").Value, Range("Months"), 0), "B")
    If IsEmpty(LastCell.Value) Then
      LastCell.PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, _
        SkipBlanks:=False, Transpose:=False
    ElseIf MsgBox("Do you want to overwrite?", vbYesNo) = vbYes Then
      LastCell.PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, _
        SkipBlanks:=False, Transpose:=False
    End If
    Application.CutCopyMode = False
  End With
  LastCell.Select
  Application.ScreenUpdating = True
End Sub

Δοκίμασέ το και πες μας.
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