Can I add a plus or max bundle to a previously purchased ticket?

[risky]

Our online corporate travel portal has changed again, and the JQ plus and max fare options are not listed. Is it possible to add plus or max to a ticket purchased previously? Previous discussion from years ago seemed to indicate it was then (after a long period of not being possible), but a lot has changed, and I couldn't find anything that says you could.

 

[aikman]

You can change your fare into a fare with a bundle.

You have to pay the change fee ($70 per flight for domestic), the fare difference at today's prices and the bundle. It may not be worth in the end.