4 free nights for the Reserve? Are you sure? The way I understand it is you get 2 free weekend nights upon meeting spend, then one night on your anniversary date. You get Diamond status after $40K spend in one calendar year. You keep Diamond status the year you earn it and the following year, so meeting $40K spend early in the first year offers the most benefits. The free night awards expire in 12 months, so have limited shelf life. I don't have a Hilton stay planned next year, so won't get the Reserve card until late 2103.