Originally Posted by
lovefreebreakfasts
You actually pay for all 4 nights, and get a statement credit for the fourth night, so it is possible that you actually get to keep the TYP for the fourth night, possibly making citi an even better deal (this wouldn't change the 4-6 nights sweet spot though). Someone who has completed a stay and received the statement credit could better comment.
Per
this post, they will credit you 3x TYP upon booking, and then remove 1X TYP upon the fourth night being refunded.