What is an interval sold that depends on availability commonly referred to as?

The term used for an interval that is sold based on availability is known as "floating time." In the context of timeshares, floating time allows owners to reserve their vacation intervals on a more flexible basis, rather than being tied to a specific week or date each year. This flexibility is beneficial for owners who may want to travel at different times based on personal schedules or preferences.

In contrast, fixed time intervals require owners to use their timeshare during a specific week each year, providing less flexibility. Scheduled time could imply a more structured booking system but does not specifically denote availability based on the owner's discretion. Open time generally refers to a set of arrangements where owners can choose their time without prior commitment but is not the formal term commonly used in industry literature. Thus, floating time accurately describes the concept of intervals sold that depend on availability.