Here's an example of a 7up bottle that VERY likely had the 0 (zero) added to the mold of a bottle that was actually made in 1945. Offset numbers like the zero on this 7up bottle were rarely if ever because of some type of an accident by the mold engraver and were done intentionally for quality control purposes.

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Name:	7up Bottle Base With Date Code Number Changed From 1945 to 1950.jpg 
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