A continuing issue that is costing people money. If you have paid for EBCI, you loose that money if you cancel the flight. However, if you want to change the flight and the new flight costs more money, the website will not allow you to pay for the additional costs with TTF. So you have a choice, cancel the first flight and loose your EBCI payment and rebook and pay the additional costs with TTF, or change the flight but be forced to pay for the additional costs with a credit card.