Take a minute and define why you are doing the migration (purpose), what you expect to accomplish (objectives), and the limitations of the project (scope). It's a good idea to establish these parameters to keep the project focused. You certainly can update these sections of the action plan, but they need to be well defined.
British Airways charges $40 to cancel or change a flight. However, in the past, this fee is only removed from your actually booking cost. Example #1: You book a domestic US flight and pay $2.50 in taxes and fees. When you cancel the flight, British Airways will return the miles but keep the $2.50.
The $180 cost to change your flight is that $150 change fee, plus the fare difference of $30. This is clearly noted in the fare rules that you agreed to when you bought the ticket, whether you are happy with it now or not.