Phil,

Welcome to Excel Fox

You can simply call the function like so

Code:
Sub OLUIR(ribbon As IRibbonUI)

    On Error Resume Next
    If Val(Application.Version) = 14 Then
        ribbon.ActivateTabMso "TabAddIns" ' For Excel 2010
    ElseIf Val(Application.Version) = 12 Then
        Application.OnTime Now(), "ActivateMyTab" 'For Excel 2007
    End If

End Sub

Sub ActivateMyTab()

    ActivateTab "Add-Ins"
    
End Sub