Sounds like a lot of fun, and a good reason to have a 20 percent night.
From an organ perspective, your liver is what deals with getting rid of alcohol, along with other toxins, and 500 other functions in the body ha. But since going PB, I can safely assume the amount of toxins (chemicals, additives, preservatives, pesticides, stress, ect...) has been reduced. Well that would not only lighten the load of the livers' task, but also improve liver health.
Improved organ health means you eliminate toxins better, so it could be that.
Here's the problem with most people drinking:
Already toxic body + strong toxin = non-functional next day
recovering body, less toxic + strong toxin = semi-functional next day