I still don't see how the following heading is relevant. If I see a Heading 4 on this page then it might still be preceded by any heading level (although a Heading 1 or 2 would indicate poor document structure).
Have a look at the following attempt at understanding your requirement. This would need to be modified further to name the bookmark created uniquely but I believe it contains all the elements to get you going. You are not going to get a solution with the missing period if you retain the cross-ref but you could choose to unlink it and then add the period into the right position. I would also recommend you create a specific style for this continuation paragraph which includes a 'page break before' setting otherwise it will often end up on the preceding page.
Code:
Sub ProofOfConcept()
'macro by Andrew Lockton
Dim aRng As Range
Set aRng = ActiveDocument.Bookmarks("\page").Range
aRng.InsertParagraphBefore
With aRng.Paragraphs(1)
.Style = "Normal"
.OutlinePromote
Debug.Print .OutlineLevel
If .OutlineLevel > 3 Then
.Style = "Normal"
aRng.Collapse Direction:=wdCollapseStart
aRng.Select
Selection.GoTo What:=wdGoToHeading, Which:=wdGoToPrevious, Count:=1
ActiveDocument.Bookmarks.Add Name:="ABC", Range:=Selection.Range
aRng.InsertAfter " continued"
aRng.Collapse Direction:=wdCollapseStart
ActiveDocument.Fields.Add Range:=aRng, Text:="Ref ABC \w \h"
aRng.Select
Else
aRng.Paragraphs(1).Range.Delete
End If
End With
End Sub