We'll see if we can obtain specific information on Batch #23. In the meantime, here's some background info on this brand - Courtesy of Aberlour:
A’bunadh, is a cask strength whisky, matured only in sherry casks, it is non – chill filtered, just as it would have been over a 100 years ago. You will also note there is no age statement on the bottle, which again was standard practice back in the late 1800s. The a’bunadh is not a limited edition whisky, but it is limited by the batch, each batch will differ slightly in strength, as we strive to consistently recapture the taste. We are currrently on batch number 24 (this was as of 2009). Each batch of a’bunadh will consist of around 50 oloroso sherry casks, varying in age from around 10yo through to 18yo.