You should keep calling- daily, if you are within a week. Cancellations do occur. VWL has very few villas available on points right now- so there will be very few cancels also, but you never know.
There is a very limited "track record" at VWL, since it has been open for members only since Jan 14. "Upgrades" to larger accommodations are not usually available to DVC point reservations unless there are extenuating circumstances.
Keep calling and Good Luck!
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