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British Airways offers its customers the option to purchase flights up to 365 days in advance of the travel date. Within this period, many things can happen commercially and operationally that result in involuntary changes to a customer booking. e.g. the commercial planning of a seasonal schedule has not been finalised, British Airways may not operate a flight for the full-season or decides decide to use a different aircraft than originally planned. Involuntary changes may also result from a disruption of service due to bad weather conditions, strikes, technical problems or security issues.
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