JSF, Java Server Faces, Primefaces.

I am struggling to find a solution on how to change the update attribute of a <p:ajax

Scenario: A Dialog with a <p:ajax to capture the close event

    <p:dialog modal="true">
       <p:ajax event="close" update="COMPONENT IDs" 
                listener="#{bean.onClose()}" />

I would like to change the update attribute when I open the dialog.
I tried

1. using an EL expression value to get the changing attribute value from a bean.
   This does not work as the attribute value is set at first rendering and never again

2. Adding the update component IDs in the listener method of the bean:

   PrimeFaces.current().ajax().update("component IDs");
   

This works.
BUT: Not for PrimeFaces Selectors (PFS). And I need that.

Like update=”@(.mystyle)”
(I guess because in that case components are selected client sidy by jquery.)

Any ideas?
Thank you
Peter