This is what the Citi Concierge told me when I made a reservation last week. However, I will agree that the T&C don't make this clear.
Originally Posted by
ffflllyyyeeerrr
Where have you found this information?
Update: cliff9973 is correct. I was somewhat misled by the Concierge. The 4th night free benefit can now be used any number of times according to Citi customer service.^