Yes you can request before giving up your week. They put a hold on it so it looks like it has been deposited but it actually hasn't, I've used the feature and cancelled and got my week back immediately. You have to call to cancel a request.
Usually with a request first, you can only put dates in that are before you check-in day. e.g if you have 23 Nov 2024 booked, you can only request out to 23 Nov 2024, where if you deposit you can request out 2-years after the check-in date. An added benefit of Abound enrolled ownership is the ability to make a request that goes beyond the reservation date, thus increasing your chances of getting a match sooner.
A "feature" of MVC weeks ownership is the ability to string together near endless strings of consecutive week bookings from 13months ahead. Some owners do that to get prime weeks 15-18 months in advance, and then they put unwanted weeks into II. You see the effect of this when there is MVC inventory in II with a check-in date more than 12 months ahead. An extreme example of this in II now is Harbour Point on Hilton head, where there is inventory out to mid May 2025.
See below for the extract from the Abound info. I've not tried it with Sheraton or Westin ownership, but the language does refer to Abound members, so I would expect it to work. If you go this route, beware that II customer service agents may not be familiar with it, so you may need to ask to speak with the Marriott desk or a supervisor.
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