I think 24,000 points per night is the Passport Plus awards for a cat 4
hotel. This is only available for platinum and diamond members.
When an award room space for normal point awards (15,000 points per night
for a cat 4 hotel) is not available, elite members can still get a room
using this Passport Plus awards - as long as the room type at the requested
hotel is not sold out. Passport Plus awards require an additional 60% point
redemption on any hotel free night award being redeemed, so the required
points per night at a cat 4 hotel will be 24,000 points.

http://www.goldpassport.com/dbcd.asp...2#PassportPlus

FFN redemption is not valid at the HR Paris - Madeleine.