I've got a run booked for June SOF-LHR-HEL-JFK-SFO/LAS-JFK-HEL-LHR-SOF, booked through BA with BA metal for the LHR-SOF flights and BA codeshares on AA/AY metal for the rest. I've just had notifications from BA that "your flight number has changed" for the AA flights, with the BA code share indeed having changed, BT the flight times stating the same.

Looking on MMB I appear to be able to cancel for a refund, which is an option I'll be keeping in reserve. I can't select different flights though online, I'd have to phone up. My question: will I actually be able to change the flights if I phone up - will this be treated as a cancellation, or will they treat it differently given the "flight number has changed" notification?

I'd ideally like to change several of the flights to condense the trip, and to get rid of the overnight recliner from LAS-JFK.

Thanks
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