Forty to sixty minutes from confirmation to the knock, identical in every central neighbourhood and identical at every hour, is the only arrival figure this house publishes.
The arrival window is the stretch between a confirmed booking and a knock on your door. It is forty to sixty minutes anywhere in central Amsterdam, and the second half of that sentence matters more than the first: anywhere, and at any hour.
Being close to the middle of the city does not. Empty streets at four in the morning do not. The house publishes one figure for every central neighbourhood because the differences between them collapse the moment a therapist is ready and moving, and a quicker number promised to one address would only be a slower one broken at another.
Confirmation starts it, not your first message. On a booking that carries a deposit she sets off once that payment has cleared, so the sum written in the thread is worth sending promptly if the hour matters to you. A booking confirmed at 01:20 realistically means a knock between two and half past. Read against a body that is already tired, that window is short enough to be worth using rather than watching, and the note on the window at two suggests what to do with it.
Schiphol and the airport hotels are not covered by the forty to sixty minutes. Those rooms are arranged individually, with a start time and a journey time agreed with you in writing before anything is fixed, and half the fee settled in advance whatever the length. An airport booking made early in the evening goes smoothly; the same booking attempted at the last minute is asking a standing window to apply where none has been offered.
Availability, not distance, is what varies at four in the morning. Fewer therapists keep those hours than keep ten in the evening, so the choice on the roster narrows even though the window does not move. Asking for a specific therapist at that hour is a different question from asking for an hour, and the small hours entry separates the two.
Two lines settle it: where the room is, and what time you want someone at the door. The answer comes back with a name, an arrival window and the whole figure, whatever the clock says.