I just want to admit to something here. I had brewed up a tart cherry stout (7.8%ish) according to maths. This was in addition to 15 other gallons of beer I made for a buddies wedding. So crunch time comes and I force carb the 15 gallons and bottle it all up and ship it off to my buddies wedding. Sweet.
2.5 years later I'm moving out of my house and my now wife spots this fermenter in the corner of the basement. It was the tart cherry stout with a dried out airlock, tart cherries still at the bottom, and just sitting there with dust on it. I'm thinking we gotta dump it but the wife reminds me of my brewing mantra, "Drink your mistakes, they won't kill you, and you'll get plenty to think about for next time." So we keg it up and I carb it. I will say during kegging I had, erm, concerns about what I was doing. Three weeks later we pull a couple pints and taste it.
It was absolutely amazing. Yeah, it had some funk on it from the tart cherries, some sour notes, but overall was damntastic. We bottled up the remainder of the keg and put them in our cellar. Years later still going I will pull a bottle, chill it to 45f-ish, crack er open and man... It's just amazing how great it tastes.
So anyways, not recommended at all, but if a keg is a bottle and a bottle is a mini keg then I'm pretty sure as long as you got pressure, low O2, good temperatures you can stash away beer for awhile. I should note that I would never try to cellar age any lagers/wheats/pales, but for heftier ABV and especially hoppy beers (hops are preservative, yo) and darker brews you can get away with quite a bit.