Persistence will pay...........
I have experienced this problem in every instance (3 times in 12 years) where we decided to lock off our Aruba unit. Persist, and they will fix it. December 6 and Thanksgiving do not equate, and they know it.
Because we reserve a year ahead, I rarely know for certain whether we will use our 2nd bedroom. So if I call later to lock it off, I do NOT wish to give up a prime trading date. I am very explicit with the reps that I must have the same date, and I never let them make the II deposit. This year I lied and said we were planning to rent the studio to an acquaintance and MUST have the same week. This worked better, but I still experienced a 2 or 3 day delay, and spent hours on the phone, in getting written confirmation for both sides of the lock-off. Very nerve-wracking.
The result was worthwhile, as we traded our studio for a great Hawaii unit. But what a nightmare. Good luck with this issue, and keep us posted.