I Haven't seen this before but logically, it was either double printed due to human error or, perhaps, it was accidentally exported and reimported into CH to be sold there-hence a new stamp was made.

It is pure speculation but I'm not sure we'll get anything more definitive-unless anyone else has any info?

Steve

: Here is a photo of the casebook with two different "C"
: numbers...any idea why there are two numbers?
: