This option creates a bad experience for the traveller. So, as long as it can be avoided and anticipated, as much the better! In addition, the cancellation rate is one of the factors of your tour’s position on your city’s page. The more cancellations and the closer to the date of the reservation, the worse position you will have and the fewer reservations you will receive.
That’s why we always recommend you to change the time of your booking instead of cancelling it.