This sounds like a great opportunity to hijack the thread to ask something that I’ve been wondering for a while.
Suppose I poured a glass of whiskey, and let the glass out at room temperature for while – say several weeks. Long enough for it to evaporate by about half. Will it get stronger or weaker?
Anecdotal evidence. I had once made me a batch of wormwood flavoured vodka which I kept in a vessel similar to these. Unfortunately the glaze was porous enough to emulate the situation you describe, so in the end all I had was bitter water.