My guess, and its only a guess, would be that some of the soldiers asked the maker to either place a number on their badge, after showing a matching award document or that some additional badge were made at a later stage. In have a attached a photo of a badge from the first order.
It also possible that Panasiuk did this on the badges he produced....
The best and worst part in this hobby of hours is that there is always a But or If
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