ronwald,
While I don't know what timeshare resort you're talking about, I'm guessing they're all pretty much the same so if it helps at all, the following is what the management at the Towers recently told me.
You have to let them know via telephone and follow up with a fax BEFORE the next years AMFs come out, assuming your return will be effective for next years usage. They will send some kind of a letter which should be signed and witnessed by a notary and returned to them ASAP.
If you wait until after they levy next years assessment, they say they will hold you responsible for the newly assessed fees.
I've paid for and plan on using my November 2015 week so my return will be effective for the year 2016.
pat
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