Yeh a year is fine , no worries there.
I've just dug out the last of my stash from three years ago tonight , been saving it as it's the best Indica I have and very good medicine. %) Although a little dry it's still perfectly smokable and enjoyable ... has just been in a box in a ziplock bag the whole time. Plastic is porous so the bud will still dry out over time , glass is a little less porous and can be better but depends on how much 'air' it's exposed to so a small nugget in a large jar will still dry out over time.
Also , it's true that some of the THC is thought to convert into CBD when aged ... from experience this certainly seems to be the case. To me this isn't such a bad thing at all as potent sativa seems to dominate my stash around here and curing/aging it a while can really have it's benefits in the quality of high and/or medicinal effects.

Aswell it will start to degrade in potency over time ... I've heard that after a year it can start to degrade and I'm sure there has been some studies about it but I think it's pretty minimal and besides ... show me someone else who can make their stash last for so long anyway lol (Lets just say I'm quite the collector and save small amounts of variety for extended periods of time so I never get stuck with one particular option/strain ... I know of noone else who does this though). Also , it's not like burning the buds to smoke doesn't destroy much of the actives anyway ... yet we still get what's desired.
After 4000 years it seems that it's completely degraded ^ haha , but then their quality of ziplock bag back then was truly dismal :D ... The oldest find of Cannabis thought to be used for smoking puposes directly due to the other equipment found along with it was more like 2700 years I think ... whereas other finds have been linked to more passive sacraments. (burnt at alters etc). Was Indeed a Chinese Shaman but I cannot remember if he was mummified (with fabric) or not ... from memory it was the special type of clay and dry environment that preserved everything so well. The Cannabis in this find was found to be high in psychoactives.
Cheers.