For what it is worth, last month in Chicago i wa told both by GP and Hotel directly that the would rather leave rooms empty than give them away if their FFN block was filled. At one hotel they were happy to take GP points, give a government, weekend, AAA rate, but not clear the FFN. At the Park Hyatt--including day of arrival--they held firm in no FFN even though rooms would go unused (one clerk said corporate office knew my FFN would expire if unused, so no big deal to refuse to open up block for them). I was not a happy Diamond camper.