For Each c In Feuil1.Range("H2:H" & Range("H" & Application.Rows.Count).End(xlUp).Row)
Select Case c.Value
Case 1
c.Offset(0, 4) = Int(c.Offset(0, 4)) + TimeValue("11:30:00")
Case 2
c.Offset(0, 4) = Int(c.Offset(0, 4)) + TimeValue("12:00:00")
' case 3 '--------- adapter les lignes en commentaire selon besoin
' c.offset(0,4) = int(C.offset(0,4))+timevalue("14:30:00")
' case ?
' c.offset(0,4) = int(C.offset(0,4))+timevalue("?h:?m:?s")
Case Else
'----------
End Select
c.Offset(0, 4).NumberFormat = "dd mm yyyy hh:mm"
Next
End Sub