Slot Return Deadline
Airlines must not hold slots which they do not intend to operate, transfer or exchange, as this could prevent other airlines from obtaining slots. If an airline becomes aware that for whatever reason it may not be able to use a slot, or series of slots, the airline must advise the coordinator, and return any slots it knows it will not use. Unwanted slots must be returned no later than 15 January for the next Northern Summer season and no later than 15 August for the next Northern Winter season.