A good RIS is a big, high gravity beer. Fermentation on a beer like this can take quite a bit of time in the primary. Figure on at least one month to six weeks on the yeast cake followed by another month or two in the bottle/keg to condition and/or carbonate up. IMHO, the longer you let it condition, the better it will be. Many are aged a year or more and are constantly, albeit very slowly, maturing and developing.
Beer so good, it's frightening.
2014: Seven Heavens Series One: Vilon, Mystic Melomel, Skeeter Pee.