I don't understand what you're trying to do and I have a real problem with activecells and selects,
maybe something like this ?
Code:
Dim lr As Long, x As Long
With Sheets("WinShuttleUpload (2)")
lr = .Cells(Rows.Count, "I").End(xlUp).Row
For x = lr To 3 Step -1
If .Cells(x, "I") <> "" Then
.Cells(x + .Range("N" & x).Value, "I").Value = .Cells(x, "I").Value
.Cells(x, "I").ClearContents
End If
Next x
End With