I smoked some 2007 a few weeks ago at my buddies. Still very good. He dries down to a level that the buds can be destemmed in a sieve. Crumbled bud is then packed in a container so that the buds displace most of the air in the jar.
I'm playing with vacuum sealed jars now but I think it would be better to displace o2 with nitro before sealing. For a 6 month storage, just regular mason jar is fine, no need to do anything special.