I had no idea that vanilla extract could be made from soaking bean pods in vodka or brandy, or that commercial extract must be 35% alcohol. So, what does soaking it longer (say a year) do for the flavor?
Ah, I can see you’re someone who believes that anything worth doing is worth overdoing! Actually, though, maximum flavor extraction takes place in about seven weeks, so soaking the beans for a year won’t produce stronger flavor. Furthermore, if the beans aren’t fully submerged in the alcohol (i.e., exposed to air), they could mold and foul the entire batch.