How to reorder / move new pages and subform instances

I have a form that has 2 functions - show a hidden page and duplicate the Page 1 and I need to reorder the pages once the user has added an instance or shown a page. I have Form A (Page 1) that can be duplicated but the user can add in a Form C (extra page) to be attached at the end of that instance of Form A.  So it goes like this:

Form A (Page 1)

button 1 - Adds new page 2 "Form C" to end of that "Form A"

if (CompleteFormC.rawValue == 1) then   topmostSubform.FormC2.presence = "visible"   xfa.host.pageDown();
else   topmostSubform.FormC2.presence = "hidden"
endif

button 2: Adds a new instance of "Form A"

topmostSubform.FormA.instanceManager.addInstance(1);
xfa.host.pageUp();

Currently, it adds the Form C to the very end, like so:

1. Form A
2. Form A
3. Form A
4. Form C
5. Form C
6. Form C

I am trying to reorder the pages so the user can add in a Form C to every instance of Form A, like so:

1. Form A
2. Form C
3. Form A
4. Form C
5. Form A
6. Form C

It's a little complicated but I would appreciate any help at all!