We recently booked a 7-day cruise to Alaska on Holland America for May 2025. We really want to do a helicopter tour of Mendenhall Glacier. On the HAL site, the excursions are available for booking. We have been told that many tours can be booked cheaper directly through the company, or through booking sites like Viator or AlaskaShoreExcursions.com. We went to a number of booking sites and found the exact trip we want (much cheaper, as described) but there are no times available. Is this likely because it is too far in advance or because they are sold out? If they are sold out, we will book through the cruise line (and pay more). If they are not selling to the public yet, is it better to wait?
Example: https://alaskashoreexcursions.com/juneau/helicopter-glacier-walkabout