We understand that sometimes plans. Use this guide to understand how to change or cancel your flight. You may be charged a fee to modify your reservation, so always review the terms and conditions carefully before making any changes. Make changes online up to two hours before your flight. Book excess baggage, request special assistance, or reserve or change your seat. Make an offer for an upgrade or budget seat with no neighbors, update your contact information and passport details, or add your Etihad Guest membership number.