You can try using the below in the 'ThisOutlookSession' module:
Private Sub Application_NewMailEx(ByVal EntryIDCollection As String)
Dim arrIDs() As String, strSPth As String, strSTxt As String, i As Integer
Dim olItm As Object, olMl As Outlook.MailItem, olAtch As Outlook.Attachment
strSTxt = "Master Patching Schedule" ' Text to find in subject
strSPth = "C:\Users\jbloggs\Desktop\test\" ' Place to save the attachment
arrIDs = Split(EntryIDCollection, ",")
For i = LBound(arrIDs) To UBound(arrIDs)
Set olItm = Application.Session.GetItemFromID(arrIDs(i))
If TypeOf olItm Is MailItem Then
Set olMl = olItm
If InStr(olMl.Subject, strSTxt) > 0 Then
For Each olAtch In olMl.Attachments
olAtch.SaveAsFile strSPth & olAtch.FileName
Next olAtch
End If
End If
Next i
Set olAtch = Nothing
Set olMl = Nothing
Set olItm = Nothing
End Sub