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I have a British Airways booking from GLA to FCO with a stopover in LHR (booked as a single booking). The booking was a reward booking made with Avios points. My issue is that I will now be in London on the date of the first leg and therefore only require the second leg. If I don't fly the first domestic leg, will the second leg to Italy be automatically cancelled? Also, if I contact them beforehand, would there be additional charges in changing the flight?
Many thanks in advance for any answers.