Originally Posted by blenderm
If it's a special release then either the bottles are numbered or they advertise the number bottled. As a general rule I'd take it that if it's not numbered it's not a special release.
While thats good rule to follow, some distillers release number bottles for each cask.
I have a bottle Arran 12yr single sherry cask and it numbered 59 out of 278 for cask number 524. So they number the next batch 1-300 out of cask number 525 or something. And its not really a "special" release cause they release a cask every yr.