Hi
we are booked on JFK> LHR> AMS (travel completed) and return AMS> LHR stop over>JFK

My Anglophile travel companion wishes to leave AMS before our tickted flight for London (skipping the AMS>LHR segment) but again flying together as booked on LHR > JFK

If I'm alone on the AMS segment
Will BA cancel my ticket? What about our tickets from LHR>JFK?

(Apologies in advance if when II searched the forum I missed an answer)

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