Join Date: Aug 2011
Location: Barcelona, London, on a plane
Programs: IB+ Gold, TK E+, Hyatt Globalist, Marriott LTP, IHG Diamond
Posts: 14,170
IB doesn't have a formal 24-hour cancellation policy published anywhere. But it tends to follow the DOT policy for US customers - but the DOT policy requires booking at least 7 days in advance of your flight.
Consider yourself lucky if you get the taxes and surcharges refunded.