For trips done from May to October, we recommend booking up to two months in advance. For trips done from November to April, it is easier for BCS to book your trip even if you contact us on a short notice.
Then again, we encourage you to contact us in all cases. We will always be glad to try and book your trip. Since our services are highly flexible, we could work around by offering alternative packages to execute what you need despite providing the service on a short notice.