I believe it is "o"
A is the 1st, B is the 2nd and so on up to the 26th then it's all the rest to the end of the month. Also the Monday letter (they are closed Mondays) is carried over to Tuesday.
I think it's O
Good ?
O is the 15th letter. You can always drive by to see (they post it on their sign)
No clue I've heard about it but never played attention to it
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