Yes you are "possibly, probably right". The only way to know for sure is to call O and then work it out.
Two agents have now said we are better off with the deal we have. Premium econ is now 699 pp, we would lose that, we also have prep great on 7 days out of 20, we would lose that.
I think we are good, not willing to spend more time on it, but I thank you for your logical thinking.