Combo Box Filter

[dgaller]

How can I filter a combo box to show only options available in a subform I have filtered? I hope I can make this clear.

This is the start of my code:

If IsNull(Me.Combo27) Then
DoCmd.RunCommand acCmdRemoveFilterSort
DoCmd.RunMacro "Local Hx hide Filters", , ""

ElseIf Not IsNull(Me.Combo27) Then
Me.[Local Delivery Subform].Form.Filter = "([Status] =" & Me!Combo27 & ")"
Me.[Local Delivery Subform].Form.FilterOn = True
DoCmd.RunMacro "Local Hx hide Filters", , ""

I would now like to filter Comb33 on the main form based on the combo27 on the main form if 27 is not null