Originally Posted by reversethrust

I have a query that perhaps someone can answer. I purchased a Oneworld Explorer ticket with BA in Egypt 11 months ago. It concludes soon with RJ flights from Moscow to Amman to Cairo.
My question is: Can I pay the change fee and switch those two RJ flights to QR and fly Moscow to Doha to Cairo?
I ask because QR was not part of Oneworld when I originally bought my ticket.
Is such a change to QR allowed or can I only fly QR on a Oneworld Explorer ticket that was issued after Qatar Airways joined Oneworld at the end of October?
Thank you.