You speaking of wet or dry aging? Rumor was at one time for brisket was 30 days past the pack date held at regular ice box temps. Sure lower temps could double that at least. In fact have kept some for several monts and still good. Now for dry aging..nice German fella taught me a week. Put mine in perforated colander sitting on a plate with a paper towel to catch the blood. Flip it around and rinse off the blood each day. This be just stuck in the ice box open to the air. Really improves Ribeyes and Sirloin. So aint a Tri Trip part of the Sirloin? There ya go..lol.