Or:

Sub M_snb()
  sn = Sheet1.Columns(1).SpecialCells(2)
    
  With Sheets.Add(, Sheets(Sheets.Count), , "J:\download\hbc9-27-10-10_Out.csv")
    For j = 1 To UBound(sn)
      .Columns(3).Replace sn(j, 1), "", 2
    Next
    .Columns(3).SpecialCells(4).EntireRow.Delete
        
    .Cells(1).Resize(, 12) = [transpose(char(row(65:77)))]
        
    .Cells(1, 16).Resize(2) = Application.Transpose(Array(.Cells(1, 7), "C"))
    .Cells(1).CurrentRegion.AdvancedFilter 2, .Cells(1, 16).CurrentRegion, .Cells(1, 20)
    sn = .Cells(1, 20).CurrentRegion.Offset(1)
    .Cells(1, 16).CurrentRegion.ClearContents
    .Cells(1, 20).CurrentRegion.ClearContents
        
    For j = 1 To UBound(sn) - 1
      If j > 1 Then If sn(j, 1) & sn(j, 3) = sn(j - 1, 1) & sn(j - 1, 3) Then sn(j, 12) = sn(j - 1, 12)
      sn(j, 2) = "9" & sn(j, 2)
    Next
    .Columns(7).Replace "C", ""
    .Columns(7).SpecialCells(4).EntireRow.Delete
    .Cells(Rows.Count, 1).End(xlUp).Offset(1).Resize(UBound(sn), UBound(sn, 2)) = sn
    .Rows(1).ClearContents
  End With
End Sub