The one-move rule for a trip that shifts
One change of date is free when asked more than twenty-four hours before the booked time, to a date within fourteen days; the whole deposit carries across.
Trips move, and a booking made weeks ahead has to be able to move with them. The one-move rule is how it does. It allows a single change of date on any booking, with the whole deposit carried to the new date, provided two conditions are met.
The two conditions
The request reaches the thread more than twenty-four hours before the booked time, counted in Amsterdam time. And the new date falls within fourteen days of the original one. Meet both and the move costs nothing: the deposit arrives on the new date intact, and the booking carries on as before, subject to her diary being open on the evening you move to.
A second move, or a late one
A second change of date, or a first one asked for inside the final day, is not refused. It is read on the cancellation scale as if you had cancelled at that moment, and whatever the scale does not keep travels on to the new date. A second move asked for three days ahead therefore keeps nothing and carries the whole deposit; one asked for inside the last day, before she sets out, keeps half and carries the other half.
Moves that are not moves
A change of hour on the same evening is not a move of date. Nor is a change of length or a change of hotel inside Amsterdam. Each of those is handled in the thread as an ordinary change, subject to her diary.
Why fourteen days
A move is meant for a trip that slides, not for a booking parked indefinitely. Fourteen days covers a flight changed by a day, a meeting that moves a week and a return pushed back to a later fare. A trip postponed by months is better cancelled more than twenty-four hours ahead, with the whole deposit returned, and booked again when the new dates are known. The page on moving dates works through the cases.