From what i can gather, this should work but it will send the latest saved version of the workbook.

Sub Mail_workbook_Outlook_1()
    Dim OutApp As Object
    Dim OutMail As Object

    Set OutApp = CreateObject("Outlook.Application")
    Set OutMail = OutApp.CreateItem(0)

    On Error Resume Next
    With OutMail
        .to = "aa@bc.org.uk; bb@bc.org.uk"
        .CC = ""
        .BCC = ""
        .Subject = "This is the Subject line"
        .Body = "Submitted sheet"
        .Attachments.Add ActiveWorkbook.FullName
        .Display   'or use .Send
    End With
    On Error GoTo 0

    Set OutMail = Nothing
    Set OutApp = Nothing
End Sub