I can't remember if I posted this before so if I did, forgive me.
Just to add my .02 to this thread, how long does beer keep? It depends on the style. Some like IPA's you need to drink fresh. Others like Barleywines can keep for years. At a recent local club meeting I brought out barleywines that were brewed on 2014, 2015, and 2016. The 2014 was y far the best of the bunch despite the fact it was seven years old! That one also won two consecutive BOS at competitions when it was two years old. This style, as do some stouts, get better with age.
I had a glass of a tripel that I made back in April, and it definitely shows signs of oxidation. Fortunately the keg is almost empty so I don't feel bad about dumping the rest of it. It is now on my brew schedule in the next week.