Helmut pardon my ignorance by I receive errors on this test at sTmp first
because it is not defined so I did and then because I did? I had one
bookmark in document" and was expecting it to put XXXXXX etc before the
bookmark(s) - did I miss the point?

Have a look at this one, which you may adapt to your needs. I couldn't find
a 'way without deleting a bookmark and restoring it. But this is common
practise 'anyway, when filling including bookmarks with text.
'As it happens, the code works here and now on any kind of bookmark.
'I didn't care about the formatting. I'm hoping, you didn't expect a ready
to use 'solution

Sub InsertBeforeBookmark()
Dim rTmp1 As Range
Dim rtmp2 As Range
Dim sTmp As Range
Dim lTmp As Long
Dim lTmpr As Long

sTmp = "XXXXXXXXXXXXX" & vbCr               'Runtime error 91 object
variable or block variable not set???

For lTmp = 1 To 3
With ActiveDocument.Bookmarks("Start")
  lTmpr = Len(.Range)
  Set rTmp1 = .Range
  .Delete
End With

With rTmp1
  .InsertBefore sTmp
  .Start = .Start + Len(sTmp)
  .Bookmarks.Add "Start"
End With

With ActiveDocument.Bookmarks("Start")
  Set rTmp1 = .Range
  .Delete
End With

Set rtmp2 = rTmp1
With rtmp2
  .Collapse
  .Tables.Add rtmp2, 4, 4
  ' beware of linebreaks by the newsreader, rewrite it this
  .Start =
ActiveDocument.Tables(ActiveDocument.Tables.Count).Range.Characters.Last.Next.Start
  .Select ' for testing remove later
  .End = .Start + lTmpr
  Stop    ' for testing remove later
  .Select ' for testing remove later
  Stop    ' for testing remove later
  .Bookmarks.Add "Start"
End With
Next
End Sub