Expect they can trade in their week and get points for sue at other DVC resorts.
From DVCnews
http://dvcnews.com/index.php/hawaii--ko-olina-resorts-175/1289-dvc-entering-fixed-week-marketplace
"This purchase option, which DVC calls Guaranteed-week Reservations, will permit buyers to use their ownership toward other Disney Vacation Club resorts and exchanges, subject to a unique set of terms and conditions. Guaranteed-week owners have until 31 days prior to their scheduled arrival to "opt out" of the guaranteed reservation. The member will then receive the number of DVC points stated within the contract. Those points are subject to normal DVC usage guidelines, banking, borrowing and transfer rules."