The date code currently being used by Anchor Brewing Company (post-October 1991) replaces the clock-face which used to show the bottling month as one of 12 small notches around the main label. A three character code is now included on the new back label of the bottle. The code works like this:

The first character is always numeric and represents the last digit of the year. The second character is always alpha and represents the month by using the first letter in a month which has not been previously used. Such as:
January: J July: L
February: F August: G
March: M September: S
April: A October: 0
May: Y November: N
June: U December: D

The third character in the code is either alpha or numeric and tells the day of the month. The first 26 days are represented by the alphabet with the remaining days listed as:
27th through 29th = 7 through 9
30th = 3
31st = 1

"0" (zero) isn't used for the 30th because the labeler makes its "Os" (letter 0) the same way it makes its "0s" (zeros).

An example would be: January 20, 2002 = 2JT

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