Private Sub CommandButton1_Click()
Dim col As Integer, lig As Integer
With Sheets("PLANNING")
col = 2 + ((Month(CDate(TextBox3.Text)) - 1) * 3)
lig = Day(CDate(TextBox3.Text)) + 4
plage = .Range("B5:AI35").Address(0, 0)
End With
Cells(lig, col + 1).Value = Me.TextBox1.Value
End Sub